Agallon of gasoline cost 30 cents in 1960 and $1.30 in 1980. what was the percent increase in the price of gasoline

A gallon of gasoline cost 30 cents in 1960 an 
$1.30 in 1980
percent increase in the price = ?
first we have to convert cents into dollars so that both amounts have to be in same unit
30 cents = $0.3
increase in gasoline cost = $1.30 - 0.3 = $1
now for calculating percent increase divide this with the new amount and than multiply with 100
percent increase = ($1 / $1.30) x 100 = 76.92% = 77% approx.
so, there is 77% increase in the price of gasoline

Intersecting secant-tangent theorem states that if a tangent segment and a secant segment are drawn to a circle from an exterior point, then the square of the measure of the tangent segment is equal to the product of the measures of the secant segment and its external secant segment.so to break it down: 1. pq acts as the tangent and ps as the secant with an intersection at p.sr = 21rp = 3x + 3pq = 4x + 4following to equation: tangent squared = the two segments multiplied by each otherso (4x + 4) ^ 2 = (3x + 3) • (21) simplifies to 16x^2 - 31x - 47 = 0 or (16x - 47)(x + 1) x = -1 or x = 47/162. pq acts as the tangent and ps as the secant with an intersection at p (again! )sr = 16rp = xpq = 15(15) ^ 2 = 16 • x225 = 16xx = 225/163. the interesting chords are proportional to each other so a ratio is possible to set up: ap dp 10 3 + x = = —— = pc pb 8 xcross multiple to get 10x = (3 + x)(8)x = 12