Determine the fraction of money the youngest boy received.

The youngest boy received $\frac{1}{2}$ of the total money.

The remainder is the total money minus the youngest boy's share.

So, $\frac{1}{2}$ of the total money remained.

The next boy received $\frac{1}{4}$ of the remainder.

So, the next boy received $\frac{1}{8}$ of the total money.

The eldest boy received the remaining money. This is the remainder from Step 2 minus the next boy's share.

To subtract these fractions, find a common denominator, which is 8.

The eldest boy received $\frac{3}{8}$ of the total money.