Answer
The number of cars manufactured in the US is 8086 per day.
The number of cars manufactured in Germany is 16172 per day.
Work Step by Step
Let $u$ be the number of cars manufactured in the US.
The number of cars manufactured in Germany is $2u$.
$u+2u=24258$ $\longrightarrow$combine like terms
$3u=24258$ $\longrightarrow$multiplication property
$3u\div3=24258\div3$ $\longrightarrow$simplify
$u=8086$
$2u=2\times8086=16172$
