A new cell phone was $625 but it was reduced to $500. What was the percent of decrease?

80%

Step-by-step explanation:

To find percent decrease (new amount/original amount)*100

(500/625)*100

=80

--

to check

625*.80  

=500

or

625*80%

=500

step-by-step explanation:

there is a formula i can give you:

it is r^2*n*sin(360/n) divided by 2 where r represents the "radius" and n is the number of sides.

plug them in:

(10sqrt(3))^2*6*sin(360/6) divided by 2

100*3*6*sin(60) divided by 2

900*sin(60)

900*sqrt(3)/2

450*sqrt(3)

approx is 779.4 cm^2