Question

A lake is 200 feet wide. Two boats start to move towards one another from opposite shores. In one minute, the first boat goes 40 feet, and the second boat goes 30 feet (they are very slow!).

Answer 1

I use faction

Explanation:

The first boat.

`(40 feet)/(60 seconds)` ÷ 10 =
`(4 feet)/(6 seconds)`

`(4 feet)/(6 seconds)` ÷ 2 =
`(2 feet)/(3 seconds)`

The first boat move
`(2 feet)/(3 seconds)`

The second one do the same

`(30 feet)/(60 seconds)` ÷ 10 =
`(3 feet)/(6 seconds)`

`(3 feet)/(6 seconds)` ÷ 2 =
`(1.5 feet)/(3 seconds)`

That is the speed of each boat.

The first boat need 50 minutes to get to the other side

2000 ÷ 2 =1000

1000 x 3 = 3000

3000 ÷ 60 = 50

The second boat need 66.6666666667 minutes to get to the other side

200 ÷1.5 = 1333.33333333

1333.33333333 x 3 = 4000

4000 ÷ 60 = 66.6666666667