If x is the number of packs of 8 socks and y the number of packs of 24 socks, then, based on the given information you can write the following system of equations:
8x + 24y = 136 total number of socks bought
x + y = 11 number of packs
To determine the number of socks in packs of 8, solve the previous system of equations. Proceed as follow:
Solve for y in the second equation:
y = 11 - x
Replace the previous expression into the first equation and solve for x:
8x + 24y = 136
8x + 24(11 - x) = 136
8x + 264 - 24x = 136 simplify like terms
-16x = 136 - 264
-16x = -128 divide by 16 both sides
x = 128/16
x = 8
And for y you obtain:
y = 11 - x
y = 11 - 8
y = 3
Hence, there are 8x = 8(8) = 64 socks in packs of 8
