Bootin D.A.

In January, 1 dollar could buy 40 bolts or 60 pins. In February, bolts and pins were sold in sets of 25 bolts and 25 pins for 1 dollar per set. To assemble a tractor, 600 bolts and 600 pins are required.

In which month was the assembly of the tractor more expensive, if other costs did not change?
In January, $10 was spent on 600 pins and $15 on 600 screws, which totals $25. In February, however, 24 sets of 25 screws and 25 pins each need to be purchased. Therefore, the tractor assembly in January is $1 more expensive.

## Answer

In January.

## Problem