CEMC Cayley, 2023

Algebra Difficulty 2.3 Junior Find the answer Canada

Charlie is making a necklace with yellow beads and green beads.
She has already used 4 green beads and 0 yellow beads. How many yellow
beads will she have to add so that $\frac{4}{5}$ of the total number of beads
are yellow?

Pick one

Solution

If $\frac{4}{5}$ of the beads
are yellow, then $\frac{1}{5}$ are
green.

Since there are 4 green beads, the total number of beads must be $4 \times 5 = 20$ .

Thus, Charlie needs to add $20 - 4 = 16$ yellow beads.

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