Misconception multiplying by the same number to both fractions

The video tutorial explains how to add fractions by finding common denominators. It highlights common mistakes students make, such as using the same multiple for both fractions, and demonstrates the correct method using an example with fractions 3/8 and 2/5. The tutorial emphasizes the importance of multiplying each fraction by the correct multiple to achieve a common denominator, resulting in the correct sum of 31/40.

Why is it important to find a common denominator when adding fractions?

• To ensure the fractions have the same numerator

• To make the fractions easier to multiply

• To make the fractions easier to subtract

• To ensure the fractions have the same denominator

What is a common mistake students make when finding a common multiple for fractions?

• Using the same multiple for both fractions

• Subtracting the fractions instead of adding

• Adding the fractions without any common multiple

• Multiplying the numerators instead of denominators

How do you find the lowest common multiple of 8 and 5?

• By subtracting 5 from 8

• By listing multiples and finding the smallest common one

• By multiplying 8 and 5

• By adding 8 and 5

What should you multiply 3/8 by to get a denominator of 40?

• 5

• 8

• 3

• 10

What is the correct sum of 3/8 and 2/5 when using the lowest common multiple?

• 30/40

• 31/40

• 25/40

• 35/40