1. at the grocery store checkout, you watch at the register as it rings up your purchases and coupons. the prices were as follows: $2.95 $1.19 $4.61 $1.74 $3.04 $8.83 $1.16 – $0.75 (coupon) – $1.00 (coupon) the register gives your total bill as $21.77. estimate the total amount of the bill and use your answer to determine whether the total on the register is reasonable.