Answer the following question, with explanation first.
Jeff is collecting matchbox cars. He has twice as many cars as trucks. He has 60 total vehicles. How many trucks does he have?

20
The number of trucks + 2(number of trucks) = 60.

Therefore 3(number of trucks) = 60.

Number of trucks = 20 because 60 / 3 = 20.

.

The answer: 20