well...
15 x 20 = 300
300+85 = 385
you can get 20 watches for $385
The lowest term of 836/54 is 418/27!
Let's start with 17 seats and just bikes. That is 34 wheeles. Now, each bike we replace with a go-kart will add 2(because we take away 2 and add 4). We need to add 14 wheels. This means we will replace 7 bikes with go-karts. 7 go-karts (28 wheels) and 10 bikes (20 wheels) is the answer.