### Home > CCA > Chapter 6 > Lesson 6.2.2 > Problem6-76

6-76.

During a two-month period gasoline increased from $4.10 per gallon to$4.35 per gallon. Assuming prices increased in a geometric sequence, what was the monthly multiplier and what was the percent increase?

To find the monthly multiplier, write an equation and solve for the variable.

New price = (original price)(multiplier for month 1)(multiplier for month 2)

$4.35 =$4.10(x)(x) or $4.35 =$4.10x2

$\frac{\4.35}{\4.10\ }=x^2$

$x=\sqrt{\frac{4.35}{4.10}}$

x ≈ 1.03 Therefore the percent increase is 3%.