A library has 167 trees on their property, but they are having trouble growing grass so they need to pay to have trees cut down each year until the property has less than 50 trees. If they can pay to have only four trees cut down this year, but eight trees cut down every year after that, in how many years will they have less than 50 trees on their property?

15 years

Step-by-step explanation:

Given:

Building inequality:

Adding current year to 14 we get 15 years as answer

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.