Question

Which of the following results in a sum or a product that is rational choose all that apply

Answer 1

Question 1: We have to identify which of given expressions are rational expressions.

1.  $3.12 \times 1.4$

= 4.368

= $\frac{4368}{1000}$

This is expressed in the form of $\frac{p}{q}$ where p and q are integers, where q is not equal to zero.

Hence, it is rational.

2. $\sqrt 9 \times \sqrt 25$

= $3 \times 5$

= 15

= $\frac{15}{1}$ which is also expressed in the form of $\frac{p}{q}$ where p and q are integers, where q is not equal to zero.

Hence, it is rational.

3. $\sqrt 2 \times \sqrt 3$

= $\sqrt 6$

which can not be expressed in the form of $\frac{p}{q}$ where p and q are integers and q is not equal to zero.

Hence, it is not rational.

4. 4+5

= 9

= $\frac{9}{1}$ which is also expressed in the form of $\frac{p}{q}$ where p and q are integers, where q is not equal to zero.

Hence, it is rational.

5. $n \times 3$

This expression can be rational and can not be rational. It depends on the value of 'n'.

Question 2:

Molli purchased 9 apples for $3.96.

Then, Molli divided $3.96 by 9.

Since, the cost of 9 apples = $3.96

If we have to find the cost of 1 apple, then we will divide the cost of 9 apples by the number of apples purchased.

Therefore, Cost of 1 apple = $3.96 $\div 9$

= 0.44

Therefore, Molli divided $3.96 by 9 in order to find out how much she paid per apple.

Therefore, Option 1 is the correct answer.