Set up a proprtion and cross multiply.
18/7.5=22/4x+1
7.5×22=18 (4x+1)
165=72x+18
147=72x
x=2.04
Answer:
31.25 percent increase
Step-by-step explanation:
To find the percent increase, we take
percent increase = (new - original)/new * 100 percent
= (420-320)/320 * 100 percent
100/320 * 100 percent
.3125 * 100 percent
31.25 percent increase
Answer:
Car 1 : 40 miles per gallon
Car 2: 25 miles per gallon
Step-by-step explanation:
family has two cars. During one particular week, the first car consumed 15 gallons of gas. The second car consumed 25 gallons of gas. The two cars Drove a combined total of 1475 miles and the sum of their fuel efficiency was 65 miles per gallon. What were the fuel efficiency of each of the cars that week
Given that :
Fuel efficiency , car 1 = x
Fuel efficiency , car 2 = y
x + y = 65 - - (1)
15x + 35y = 1475 - - - (2)
x = 65 - y
15(65-y) + 35y
975 - 15y + 35y = 1475
20y = 14875 - 975
20y = 500
y = 25
Put y = 25 in (1)
x + y = 65
x + 25 = 65
x = 65 - 25
x = 40
Get the x terms by themselves on one side and a constant on the other side of the equal sign...
4x^2-8x=1 make the leading coefficient equal to one...
x^2-2x=1/4 now halve the linear coefficient, -2 in this case, square it, and add that value to both sides of the equation...-2/2=-1, -1^2=1 so
x^2-2x+1=1+1/4
x^2-2x+1=5/4 now the left side is a perfect square...
(x-1)^2=5/4 take the square root of both sides...
x-1=±√(5/4) add 1 to both sides
x=1±√(5/4)
