SOLUTION: Anna drives 45 km to work. If she increases her usual average speed by 5 km/h, the time it takes her to drive to to work is decreased by 6 minutes. Find her usual speed

Question 1167532: Anna drives 45 km to work. If she increases her usual average speed by 5 km/h, the time it takes her to drive to to work is decreased by 6 minutes. Find her usual speed
Answer by ikleyn(52776) (Show Source): You can put this solution on YOUR website!
.


Use and solve this "time" equation


     -  =   of an hour  (= 6 minutes).


It is equivalent to

     -  = 1     (1)


and has an obvious solution  x = 45.



CHECK.    -  =  -  = 10 - 9 = 1.    ! Correct !


Alternatively, you can reduce the equation (1) to quadratic equation and solve it formally.

Solved.

RELATED QUESTIONS
If Alexandra increases her usual driving speed by 15 km/h, it will take her 2h less to... (answered by mananth)

Hoi Ching drives to work in 35 minutes. If she increases her average speed by 5km/h, she... (answered by stanbon)

Libby drive to work 1 hour. If she increases her average speed by 10 miles per hour, the... (answered by addingup,Alan3354,ikleyn,MathTherapy)

if Sarah takes 45minutes to drive to work everyday. if the distance travelled from her... (answered by Cromlix)

the time it takes to travel a certain distance varies inversely as the rate of speed. if... (answered by josmiceli)

Sandra takes 6 hours to drive 300 miles. If she increases her speed 5 mi/h, how many... (answered by ramkikk66)

Charlotte walks to work every morning. It takes 40 minutes if she walks at 4.5 km/h. How... (answered by ewatrrr)

Erin rides her bike from home to school in 15 minutes. If she increases her speed by 5... (answered by josmiceli)

1) Stan has 14 bills in his wallet worth $95 altogether. If the wallet contains only $5... (answered by addingup)