Scroll:Fractions >> Least common denominator >> saq (3810)
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)
What is the least common denominator of
2
5
and
9
10
Answer:_______________
2)
What is the least common denominator of
4
9
and
1
3
Answer:_______________
3)
What is the least common denominator of
3
4
and
1
6
Answer:_______________
4)
What is the least common denominator of
3
4
and
5
12
Answer:_______________
5)
What is the least common denominator of
1
12
and
1
2
Answer:_______________
6)
What is the least common denominator of
1
3
and
11
12
Answer:_______________
7)
What is the least common denominator of
3
8
and
3
4
Answer:_______________
8)
What is the least common denominator of
1
2
and
3
4
Answer:_______________
9)
What is the least common denominator of
7
12
and
3
8
Answer:_______________
10)
What is the least common denominator of
7
12
and
1
6
Answer:_______________
1)
What is the least common denominator of
2
5
and
9
10
Answer: 10
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 5 and 10. Find the least common multiple of 5 and 10.
Write the prime factorisation for each number. 5 is a prime number. You do not need to factorise 5.
5 = 5 10 = 2 × 5
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 5 = 10
The least common multiple of 5 and 10 is 10.
The least common denominator of
2
5
and
9
10
is 10.
2)
What is the least common denominator of
4
9
and
1
3
Answer: 9
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 9 and 3. Find the least common multiple of 9 and 3.
Write the prime factorisation for each number. 3 is a prime number. You do not need to factorise 3.
9 = 3 × 3 3
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
3 × 3 = 9
The least common multiple of 9 and 3 is 9.
The least common denominator of
4
9
and
1
3
is 9.
3)
What is the least common denominator of
3
4
and
1
6
Answer: 12
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 4 and 6. Find the least common multiple of 4 and 6.
Write the prime factorisation for each number.
4 = 2 × 2 6 = 2 × 3
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 3 = 12
The least common multiple of 4 and 6 is 12.
The least common denominator of
3
4
and
1
6
is 12.
4)
What is the least common denominator of
3
4
and
5
12
Answer: 12
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 4 and 12. Find the least common multiple of 4 and 12.
Write the prime factorisation for each number.
4 = 2 × 2 12 = 2 × 2 × 3
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 3 = 12
The least common multiple of 4 and 12 is 12.
The least common denominator of
3
4
and
5
12
is 12.
5)
What is the least common denominator of
1
12
and
1
2
Answer: 12
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Slove:
The denominators are 12 and 2. Find the least common multiple of 12 and 2.
Write the prime factorisation for each number. 2 is a prime number. You do not need to factorise 2.
12 = 2 × 2 × 3 2
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 3 = 12
The least common multiple of 12 and 2 is 12.
The least common denominator of
1
12
and
1
2
is 12.
6)
What is the least common denominator of
1
3
and
11
12
Answer: 12
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 3 and 12. Find the least common multiple of 3 and 12.
Write the prime factorisation for each number. 3 is a prime number. You do not need to factorise 3.
3 12 = 2 × 2 × 3
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 3 = 12
The least common multiple of 3 and 12 is 12.
The least common denominator of
1
3
and
11
12
is 12.
7)
What is the least common denominator of
3
8
and
3
4
Answer: 8
SOLUTION 1 :
Remember
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 8 and 4. Find the least common multiple of 8 and 4.
Write the prime factorisation for each number.
8 = 2 × 2 × 2 4 = 2 × 2
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 2 = 8
The least common multiple of 8 and 4 is 8.
The least common denominator of
3
8
and
3
4
is 8.
SOLUTION 2 :
Remember
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 8 and 4. Find the least common multiple of 8 and 4.
Write the prime factorisation for each number.
8 = 2 × 2 × 2 4 = 2 × 2
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 2 = 8
The least common multiple of 8 and 4 is 8.
The least common denominator of
3
8
and
3
4
is 8.
8)
What is the least common denominator of
1
2
and
3
4
Answer: 4
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 2 and 4. Find the least common multiple of 2 and 4.
Write the prime factorisation for each number. 2 is a prime number. You do not need to factorise 2.
2 4 = 2 × 2
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 = 4
The least common multiple of 2 and 4 is 4.
The least common denominator of
1
2
and
3
4
is 4.
9)
What is the least common denominator of
7
12
and
3
8
Answer: 24
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 12 and 8. Find the least common multiple of 12 and 8.
Write the prime factorisation for each number.
12 = 2 × 2 × 3 8 = 2 × 2 × 2
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.
2 × 2 × 2 × 3 = 24
The least common multiple of 12 and 8 is 24.
The least common denominator of
7
12
and
3
8
is 24.
10)
What is the least common denominator of
7
12
and
1
6
Answer: 12
SOLUTION 1 :
Remember:
The least common denominator is the least common multiple of the denominators.
Solve:
The denominators are 12 and 6. Find the least common multiple of 12 and 6.
Write the prime factorisation for each number.
12 = 2 × 2 × 3 6 = 2 × 3
Repeat each prime factor the greatest number of times it appears in any of the prime factorisations above.