Sasi Math (Revised for 1024)

Scroll:Distance, Time and Speed >> Distance, Time & Speed >> ps (689)

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.

A motorist travelled $\frac{2}{5}$ of his journey at 126 $\frac{km}{h.}$ After which, he changed his speed to 108 $\frac{km}{h}$ and completed the rest of his journey in 3 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 100 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 400 km at 80 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 95 $\frac{km}{h.}$ After which, he changed his speed to 114 $\frac{km}{h}$ and completed the rest of his journey in 2 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 75 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 300 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 119 $\frac{km}{h.}$ After which, he changed his speed to 102 $\frac{km}{h}$ and completed the rest of his journey in 3 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 60 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 480 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 55 $\frac{km}{h.}$ After which, he changed his speed to 66 $\frac{km}{h}$ and completed the rest of his journey in 2 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 60 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 480 km at 80 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 70 $\frac{km}{h.}$ After which, he changed his speed to 84 $\frac{km}{h}$ and completed the rest of his journey in 2 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

10)

Mr Lim drove at 30 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 120 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

Answer: 8.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	108 km
	3 $\frac{1}{2}$ h	ï»¿→	3 $\frac{1}{2}$ x 108 km
		=	378 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	378 km
	$\frac{1}{5}$ of the journey	ï»¿→	378 km ÷ 3
		=	126 km
	$\frac{2}{5}$ of the journey	→	2 x 126 km
		=	252 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	252 km ÷ 126 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	3 $\frac{1}{2}$ h + 2 h
		=	5 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 5 $\frac{1}{2}$ h
		=	8.00 a.m.

Answer: 83.33 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 400 km	→	400 km ÷ 80 $\frac{km}{h}$
		ï»¿=	5 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	400 km
	$\frac{1}{5}$ of the journey	→	400 km ÷ 4
		=	100 km
	$\frac{5}{5}$ of the journey	→	5 x 100 km
		=	500 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	100 km ÷ 100 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	5 h + 1 h
		=	6 h

Step 6:	Average speed	→	500 km ÷ 6 h
		=	83.33333 $\frac{km}{h}$
		≈	83.33 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	114 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 114 km
		=	285 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	285 km
	$\frac{1}{5}$ of the journey	ï»¿→	285 km ÷ 3
		=	95 km
	$\frac{2}{5}$ of the journey	→	2 x 95 km
		=	190 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	190 km ÷ 95 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	2 $\frac{1}{2}$ h + 2 h
		=	4 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 4 $\frac{1}{2}$ h
		=	9.00 a.m.

Answer: 62.50 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 300 km	→	300 km ÷ 60 $\frac{km}{h}$
		ï»¿=	5 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	300 km
	$\frac{1}{5}$ of the journey	→	300 km ÷ 4
		=	75 km
	$\frac{5}{5}$ of the journey	→	5 x 75 km
		=	375 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	75 km ÷ 75 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	5 h + 1 h
		=	6 h

Step 6:	Average speed	→	375 km ÷ 6 h
		=	62.5 $\frac{km}{h}$
		≈	62.50 $\frac{km}{h}$

Answer: 8.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	102 km
	3 $\frac{1}{2}$ h	ï»¿→	3 $\frac{1}{2}$ x 102 km
		=	357 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	357 km
	$\frac{1}{5}$ of the journey	ï»¿→	357 km ÷ 3
		=	119 km
	$\frac{2}{5}$ of the journey	→	2 x 119 km
		=	238 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	238 km ÷ 119 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	3 $\frac{1}{2}$ h + 2 h
		=	5 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 5 $\frac{1}{2}$ h
		=	8.00 a.m.

Answer: 60.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 480 km	→	480 km ÷ 60 $\frac{km}{h}$
		ï»¿=	8 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	480 km
	$\frac{1}{5}$ of the journey	→	480 km ÷ 4
		=	120 km
	$\frac{5}{5}$ of the journey	→	5 x 120 km
		=	600 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	120 km ÷ 60 $\frac{km}{h}$
		=	2 h

Step 5:	Total time for the whole journey	→	8 h + 2 h
		=	10 h

Step 6:	Average speed	→	600 km ÷ 10 h
		=	60 $\frac{km}{h}$
		≈	60.00 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	66 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 66 km
		=	165 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	165 km
	$\frac{1}{5}$ of the journey	ï»¿→	165 km ÷ 3
		=	55 km
	$\frac{2}{5}$ of the journey	→	2 x 55 km
		=	110 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	110 km ÷ 55 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	2 $\frac{1}{2}$ h + 2 h
		=	4 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 4 $\frac{1}{2}$ h
		=	9.00 a.m.

Answer: 75.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 480 km	→	480 km ÷ 80 $\frac{km}{h}$
		ï»¿=	6 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	480 km
	$\frac{1}{5}$ of the journey	→	480 km ÷ 4
		=	120 km
	$\frac{5}{5}$ of the journey	→	5 x 120 km
		=	600 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	120 km ÷ 60 $\frac{km}{h}$
		=	2 h

Step 5:	Total time for the whole journey	→	6 h + 2 h
		=	8 h

Step 6:	Average speed	→	600 km ÷ 8 h
		=	75 $\frac{km}{h}$
		≈	75.00 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	84 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 84 km
		=	210 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	210 km
	$\frac{1}{5}$ of the journey	ï»¿→	210 km ÷ 3
		=	70 km
	$\frac{2}{5}$ of the journey	→	2 x 70 km
		=	140 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	140 km ÷ 70 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	2 $\frac{1}{2}$ h + 2 h
		=	4 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 4 $\frac{1}{2}$ h
		=	9.00 a.m.

10)

Answer: 50.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 120 km	→	120 km ÷ 60 $\frac{km}{h}$
		ï»¿=	2 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	120 km
	$\frac{1}{5}$ of the journey	→	120 km ÷ 4
		=	30 km
	$\frac{5}{5}$ of the journey	→	5 x 30 km
		=	150 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	30 km ÷ 30 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	2 h + 1 h
		=	3 h

Step 6:	Average speed	→	150 km ÷ 3 h
		=	50 $\frac{km}{h}$
		≈	50.00 $\frac{km}{h}$