posted by cassie on .
1. A car travels 20 kilometers per hour faster than a second car. The first car covers 180 kilometers in the same time the second covers 135 kilometers. What is the average speed of each car?
2. The tens' digit of a two-digit number is one more than its units' digit. If the number is divided by the sum of the digits, the quotient. What is the number?
180=F*t and 135=S*t or 180=F*135/S or
S=135/180 F put that into the first equation.
2. Makes no sense to me.
speed of 2nd car -- x
speed of 1st car -- x+20
time for 2nd car to go 135 km = 135/x
time for 1st car to go 180 km = 180/(x+20)
but aren't these two the same ?
In the second question, it looks like you did not finish the part where it tells us what the quotient is.
let unit's digit be x
then tens digit is x+1
then the number is 10(x+1) + x = 11x + 10
so (11x+10)/(x+(x+1)) = the quotient