First, determine the difference between the amount Percy paid and the price of the basketball. That is, $24.10 - $22.99 = $1.11. Divide this value by the price of the basketball and multiply the quotient by 100% to get the tax rate. ($1.11 / $22.99) x 100% = 4.8% Thus, the sales tax is approximately equal to 4.8%.
The sequence is to multiply by -3. Therefore, you want to multiply by -3 which gives you 108. Since it is a negative by a positive the answer would be negative. The next term would be -108.