COOKIE64:

Please help


Irene had a total of 1686 red blue and green balloons for sale .

The ratio of the number of red balloons to the number of blue balloons was 2:3

After Irene sold 3/4 of the blue balloons and 1/2 of the green balloons and none of the red balloons she had 922 balloons left

How many blue balloons did Irene have at first?

You can refer to
http://www.onsponge.com/forum/35-thinki ... g-unchaned

Before
Red : Blue
2 : 3
Multiply by 4
8 : 12

Red -> 8 units
Blue -> 12 units
Green -> 2 parts

Change
Irene sold 3/4 of the balloons,1/2 of the green balloons and none of the red balloons.

After
Red -> 8 units
Blue -> 1/4x12 = 3 units
Green -> 1/2x2 parts = 1 part

At first, total of 1686 red,blue,green balloons -> 8u+12u+2p = 1686
20u+2p = 1686 - (1)

In the end, 922 balloons left -> 8u+3u+p = 922
11u+p = 922
Multiply by 2
22u+2p = 1844 - (2)

(2)-(1)
2u = 158

Number of blue balloons that Irene had at first = 12u = 158/2x12 = 948