Item 5 A bag contains 6 red marbles. The ratio of red marbles to blue marbles is 2 for every 5. Find the number of blue marbles in the bag. Item 5 A bag contains 6 red marbles. The ratio of red marbles to blue marbles is 2 for every 5. Find the number of blue marbles in the bag.

15 blue marbles

Step-by-step explanation:

Given that:

A bag contains 6 red marbles.

The Ratio of red to  blue marbles is 2:5

Thus, the ratio of red marbles for 6 red marbles in a bag will be = 6/2 = 3

Now; the ratio of blue marbles in a bag containing 6 red marbles = 3 × 5 = 15 blue marbles

OR

Mathematically;

So, we are looking for the same number we can multiply for both the numerator and the denominator that can give us the value of 6 in the above numerator to determine the value of the denominator. If we use 3 since 2× 3 = 6

We have:

So, there are 15 blue marbles in the bag.

a. is correct