Scroll:Percentage >> Multiplication in Percentage >> ps (2902)


Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.



 

1)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 20%, there are now 285 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




2)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 24%, there are now 245 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




3)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 34%, there are now 145 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




4)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 47%, there are now 216 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




5)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 54%, there are now 294 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




6)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 27%, there are now 208 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




7)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 35%, there are now 420 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




8)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 32%, there are now 114 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




9)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 53%, there are now 384 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




10)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 19%, there are now 396 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.


Answer:_______________




 

1)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 20%, there are now 285 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 1900


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →150% (at first)
Step 2: % of red marbles removed 30100 x 150%  
    = 45%  
  % of red marbles left →150% - 45%  
    = 105%  
 Step 3: % of blue marbles after the 20% increase →100% + 20%  
    = 120%  
 Step 4: Difference in % of marbles →120% - 105%  
    = 15%  
Step 5:                                      15% →285  
                                         1% 28515%  
  Number of blue marbles at the start         100% 28515% x 100%1  
    = 1900  


2)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 24%, there are now 245 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 500


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →125% (at first)
Step 2: % of red marbles removed 40100 x 125%  
    = 50%  
  % of red marbles left →125% - 50%  
    = 75%  
 Step 3: % of blue marbles after the 24% increase →100% + 24%  
    = 124%  
 Step 4: Difference in % of marbles →124% - 75%  
    = 49%  
Step 5:                                      49% →245  
                                         1% 24549%  
  Number of blue marbles at the start         100% 24549% x 100%1  
    = 500  

 



3)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 34%, there are now 145 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 500


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →150% (at first)
Step 2: % of red marbles removed 30100 x 150%  
    = 45%  
  % of red marbles left →150% - 45%  
    = 105%  
 Step 3: % of blue marbles after the 34% increase →100% + 34%  
    = 134%  
 Step 4: Difference in % of marbles →134% - 105%  
    = 29%  
Step 5:                                      29% →145  
                                         1% 14529%  
  Number of blue marbles at the start         100% 14529% x 100%1  
    = 500  


4)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 47%, there are now 216 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 300


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →125% (at first)
Step 2: % of red marbles removed 40100 x 125%  
    = 50%  
  % of red marbles left →125% - 50%  
    = 75%  
 Step 3: % of blue marbles after the 47% increase →100% + 47%  
    = 147%  
 Step 4: Difference in % of marbles →147% - 75%  
    = 72%  
Step 5:                                      72% →216  
                                         1% 21672%  
  Number of blue marbles at the start         100% 21672% x 100%1  
    = 300  

 



5)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 54%, there are now 294 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 600


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →150% (at first)
Step 2: % of red marbles removed 30100 x 150%  
    = 45%  
  % of red marbles left →150% - 45%  
    = 105%  
 Step 3: % of blue marbles after the 54% increase →100% + 54%  
    = 154%  
 Step 4: Difference in % of marbles →154% - 105%  
    = 49%  
Step 5:                                      49% →294  
                                         1% 29449%  
  Number of blue marbles at the start         100% 29449% x 100%1  
    = 600  


6)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 27%, there are now 208 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 400


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →125% (at first)
Step 2: % of red marbles removed 40100 x 125%  
    = 50%  
  % of red marbles left →125% - 50%  
    = 75%  
 Step 3: % of blue marbles after the 27% increase →100% + 27%  
    = 127%  
 Step 4: Difference in % of marbles →127% - 75%  
    = 52%  
Step 5:                                      52% →208  
                                         1% 20852%  
  Number of blue marbles at the start         100% 20852% x 100%1  
    = 400  

 



7)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 35%, there are now 420 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 1400


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →150% (at first)
Step 2: % of red marbles removed 30100 x 150%  
    = 45%  
  % of red marbles left →150% - 45%  
    = 105%  
 Step 3: % of blue marbles after the 35% increase →100% + 35%  
    = 135%  
 Step 4: Difference in % of marbles →135% - 105%  
    = 30%  
Step 5:                                      30% →420  
                                         1% 42030%  
  Number of blue marbles at the start         100% 42030% x 100%1  
    = 1400  


8)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 32%, there are now 114 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 200


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →125% (at first)
Step 2: % of red marbles removed 40100 x 125%  
    = 50%  
  % of red marbles left →125% - 50%  
    = 75%  
 Step 3: % of blue marbles after the 32% increase →100% + 32%  
    = 132%  
 Step 4: Difference in % of marbles →132% - 75%  
    = 57%  
Step 5:                                      57% →114  
                                         1% 11457%  
  Number of blue marbles at the start         100% 11457% x 100%1  
    = 200  

 



9)  

There are 50% more red marbles than blue marbles in a bag. After I removed 30% of the red marbles and increased the number of blue marbles by another 53%, there are now 384 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 800


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →150% (at first)
Step 2: % of red marbles removed 30100 x 150%  
    = 45%  
  % of red marbles left →150% - 45%  
    = 105%  
 Step 3: % of blue marbles after the 53% increase →100% + 53%  
    = 153%  
 Step 4: Difference in % of marbles →153% - 105%  
    = 48%  
Step 5:                                      48% →384  
                                         1% 38448%  
  Number of blue marbles at the start         100% 38448% x 100%1  
    = 800  


10)  

There are 25% more red marbles than blue marbles in a bag. After I removed 40% of the red marbles and increased the number of blue marbles by another 19%, there are now 396 fewer red marbles than blue marbles. Find the number of blue marbles I had at first.

Answer: 900


SOLUTION 1 :
Step 1: Blue marbles →100% (at first)
  Red marbles →125% (at first)
Step 2: % of red marbles removed 40100 x 125%  
    = 50%  
  % of red marbles left →125% - 50%  
    = 75%  
 Step 3: % of blue marbles after the 19% increase →100% + 19%  
    = 119%  
 Step 4: Difference in % of marbles →119% - 75%  
    = 44%  
Step 5:                                      44% →396  
                                         1% 39644%  
  Number of blue marbles at the start         100% 39644% x 100%1  
    = 900