Helen purchased 3 copies of a book online at a 20% discount. she paid $10 for shipping that was not discounted. write an equation that represents the cost of buying a book online. how much was the original price of one copy of the book if her total ended up being $40?

Select the correct answer from each drop-down menu. rewrite the formula to find voltage. the formula for electrical power (p, in watts) is where v is the voltage in volts and r is the resistance in ohms. for a particular brand of water heater, r is 32 ohms and p is 0.5 watts. the formula to find v is , and the voltage at which the heater operates is volts.

Aschool had an election where the candidates received votes in the ratio 1: 2: 3. if the winning candidate received 210 votes, how many total people voted in the election?

Shannon drove for 540 minutes. if she traveled 65 miles per hour, how many total miles did she travel?