Tracie and Marcia drove to Northern California to see Marcia's sister Eureka. Tracie drove one hour more than four times as much as Marcia. The trip took a total of 21 driving hours. How many hours did Tracie drive?

Tracie drove for 17 hours.

Step-by-step explanation:

Given that,

Tracie and Marcia drove to Northern California to see Marcia's sister Eureka.

Let us assume,

The number of hours drove by Marcia be 'x'. The number of hours drove by Tracie is one hour more than four times as much as Marcia.

⇒ one hour more than four times of Marcia = 1+4x

The trip took a total of 21 driving hours.

To find the number of hours Marcia drove:

⇒ Tracie hours + Marcia hours = Total hours.

⇒ (1+4x) + x = 21

⇒ 1 + 5x = 21

⇒ 5x = 20

⇒ x = 20/5

⇒ x = 4

Therefore, Marcia drove for 4 hours.

To find the number of hours Tracie drove:

Substitute x=4, in (1+4x)

⇒ 1+4 (4)

⇒ 1+16

⇒ 17 hours.

∴ Tracie drove for 17 hours.

Answer:17

Step-by-step explanation:

Take the total miles driven. minus 1 divide by 5. take that answer and multiply by 4 and add 1