Treat Jerry's stamps at first as 4 units.

So Tom has 4 units + 60 at first.

1/4 of that = (4 units + 60 stamps) ÷ 4
= 1 unit + 15 stamps

Gave ¼ to Jerry means Tom gave 1 unit and 15 stamps to Jerry.

So Jerry now has 4 units + 1 unit + 15 stamps = 5 units + 15 stamps


Tom now has 3 x (1 unit + 15 stamps)
= 3 units + 45 stamps



Tom then receives 2/5 of Jerry's stamps and 87 stamps from his uncle.

1/5 of Jerry's stamps = (5 units + 15 stamps) ÷ 5
= 1 unit + 3 stamps

2/5 of Jerry's stamps = 2 x (1 unit + 3 stamps)
= 2 units + 6 stamps

So Jerry gave 2 units + 6 stamps to Tom.

Stamps that Tom has now
= 2 units + 6 stamps + 3 units + 45 stamps + 87 stamps = 5 units + 138 stamps

But question says that he has twice his original number,which = (4 units + 60) x 2
= 8 units + 120 stamps


8 units - 5 units = 3 units

138 stamps - 120 stamps = 18 stamps

If we compare, 5 units and 120 stamps are in common. What's not common is 3 units and 18 stamps

But since the two are the same,

3 units = 18 stamps.

1 unit = 18 stamps ÷ 3 = 6 stamps


Number of stamps Jerry gave to Tom
is 2 units + 6

= 2 x 6 + 6
= 12 + 6
= 18


Number of stamps Tom had in the end
= 8 units + 120
= 8 x 6 + 120
= 48 + 120
= 168

thanks a lot

Welcome. Please check the above working again. I have edited some of the errors made earlier.