Question

Select the correct answer.

Answer 1

Answer:

He drove the rest of the trip at 30 miles per hour

Step-by-step explanation:

The rule of the distance is D = v × t, where

• v is the speed

• t is the time

∵ It is 170 miles from Bruce's house to the city where his brother lives

∴ D = 170 miles

∵ He drove for 2 hours at 55 miles per  hour

∴ t1 = 2 hours and v1 = 55 miles/hour

→ By using the rule above find the distance of this part of his trip

∴ D1 = 55 × 2 = 110 miles

∵ The rest of the trip took 2 hours

∴ t2 = 2 hours

∵ D = D1 + D2

→ Substitute the values of D and D1 to find D2

∴ 170 = 110 + D2

→ Subtract 110 from both sides to find D2

∴ 60 = D2

∴ D2 = 170 - 110 = 60 miles

∵ The rest of the trip is 60 miles

∵ It took 2 hours

∵ D2 = v2 × t2

∴ 60 = v2 × 2

→ Divide both sides by 2

∴ 30 = v2

∴ v2 = 30 miles/hour

∴ He drove the rest of the trip at 30 miles per hour