1550.41 – Cows and Oxen

Estelle spent $1705 on cows and oxen. Cows cost $40 and oxen cost $75 each. She bought twice as many cows as oxen. How many of each did she buy?

Solution

16 oxen, 32 cows. An equation, using xx for the number of oxen:

75x+2x×40=1705155x=1705x=16\begin{align*}75x + 2x \times 40 &= 1705 \\155x &= 1705 \\x &= 16\end{align*}