So x is the total number of postages. Since it can be divided into 4 and 6 it must be a multiple of 24.
X/4 - X/6 =25
(6X - 4X) / 24 = 25
2X = 600
X = 300

So lets check 300/4 = 75
300/6 = 50
75 -50 = 25

So answer is 300

If x postage stamps were divided evenly among 4 boys, each boy would receive y postage stamps. \
If each of the 4 boys has y stamps, then there are 4y stamps in total.
We can write: x = 4y

If the x postage stamps were divided evenly among 6 boys, each boy would receive z postage stamps.
If each of the 6 boys has z stamps, then there are 6z stamps in total.
We can write: x = 6z

If y - z = 25, what is the value of x?
If x = 4y, then y = x/4
If x = 6z, then z = x/6

Take y - z = 25
Replace y and z to get: x/4 - x/6 = 25
Multiply both sides by 12 (the LCM of 4 and 6) to get: 12(x/4 - x/6) = 25(12)
Simplify: 3x - 2x = 300
Simplify: x = 300

Answer: 300

Cheers,
Brent
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