Which number produces an irrational number when multiplied by 2/5?
a) 5/7
b) -5/2
c) 1.34
d) pie

The correct option is (D) pie.

Step-by-step explanation:  We are to select the correct number that produces an irrational number when multiplied by pie.

We know that if one of number is a non-zero rational number, then for the product to be irrational, we must have the other number irrational.

Give number is 2/5, which is rational. So the other number must be irrational.

Out of the given options, first three numbers are rational.

Only the last number pie is irrational. Because, the digits after the decimal are non-repeating and non-terminating.

So, the product will be irrational, if the other number is pie.

Thus, the correct option is (D).

yes

step-by-step explanation:

yes

1/3 + 1/3 ≠ 2/6 because 1/3 alone = 2/6  

step by step explanation:

1/3 + 1/3 = 2/3       2/3=4/6