Eric sold cell phones for 70 dollars eric increases his sale price by 100% what is the sales price of the cell phone

During a bike challenge riders have to collect various colored ribbons each 1/2 mile they collect a red ribbon each eighth mile they collect a green ribbon and each quarter mile they collect a blue ribbion wich colors of ribion will be collected at the 3/4 markrer

Nine more than four times a number is the same as one less than twice the number. find the number?

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers