Question

Which of the following expressions has a sum of 42/100

Answer 1

`(3)/(10)+(10)/(100)+(2)/(100)`

Explanation:

Verify each expression

case 1) we have

`(12)/(10)+(30)/(100)`

Multiply the first term by 10/10

`(120)/(100)+(30)/(100)`

Remember that

Fractions with the same denominator, you can add the numerators and write the sum over the common denominator

so

`(120)/(100)+(30)/(100)=(150)/(100)`

therefore

`(150)/(100) \\eq (42)/(100)`

case 2) we have

`(40)/(100)+(2)/(10)`

Multiply the second term by 10/10

`(40)/(100)+(20)/(100)`

Remember that

Fractions with the same denominator, you can add the numerators and write the sum over the common denominator

so

`(40)/(100)+(20)/(100)=(60)/(100)`

therefore

`(60)/(100) \\eq (42)/(100)`

case 3) we have

`(7)/(100)+(5)/(10)+(30)/(100)`

Multiply the second term by 10/10

`(7)/(100)+(50)/(100)+(30)/(100)`

Remember that

Fractions with the same denominator, you can add the numerators and write the sum over the common denominator

so

`(7)/(100)+(50)/(100)+(30)/(100)=(87)/(100)`

therefore

`(87)/(100) \\eq (42)/(100)`

case 4) we have

`(3)/(10)+(10)/(100)+(2)/(100)`

Multiply the first term by 10/10

`(30)/(100)+(10)/(100)+(2)/(100)`

Remember that

Fractions with the same denominator, you can add the numerators and write the sum over the common denominator

so

`(30)/(100)+(10)/(100)+(2)/(100)=(42)/(100)`

so

`(42)/(100)=(42)/(100)`

This expression is the answer