Hi Jessica,

Following pls find the worked solutions:

Q1.

<after>

G : B

1 : 4

Working Backwards, we have ...

<Before>

G:

1u - 32

B:

2/5 left = 4u

5/5 (at first) = 4 ÷ (2/5)

= 4 x (5/2) = 10u

Given that there were 408 B and G at first, we have...

1u - 32 + 10u --> 408

11u --> 408 + 32 = 440

1u --> 40

At first, B = 10u --> 10 x 40 = 400

At first, G = 1u - 32 --> 40 - 32 = 8

Hence, B - G = 400 - 8 = 392

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Q2.

<After>

A : B

4 : 1

<Process>

33 pkts transferred frm B to A.

Working Backwards, we have ...

A: 4u - 33

B: 1u + 33

At first, A - B = 225

Hence, we have ....

4u - 33 - 1u - 33 --> 225

3u --> 225 + 33 + 33 = 291

1u --> 291 ÷ 3 = 97

At first, A = 4u - 33 --> (4 x 97) - 33 = 355

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Trust the above helps.

Cheers,

Edward