Question

A bag contains red marbles, blue marbles and green marbles only. The ratio of the number of each marble is Red:Green:Blue=12:5:2. There are 112 more red marbles than green marbles. Work out the number of blue marbles

Answer 1

There are 14 blue marbles in the bag.

Explanation:

Let's call the number of green marbles "x". Then we know that the number of red marbles is 112 more than x, or x+112. We can use the ratio to find the number of blue marbles.

First, we need to find the total number of parts in the ratio. That's 12+5+2=19.

Next, we can use the ratio to set up an equation. The number of blue marbles is 2/19 of the total number of marbles. We can write this as:

2/19 (x + x + 112 + blue) = blue

Simplifying this equation, we get:

2x + 224 = 17blue

Now we can solve for blue:

blue = (2x + 224)/17

We know that blue is a whole number, so we need to find a value of x that makes the numerator of this fraction divisible by 17. After some trial and error, we find that x=3 works:

blue = (2(3) + 224)/17 = 14

Therefore, there are 14 blue marbles in the bag.