Me in math!

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.



2. the following formula relates three quantities: force (f), mass (m), and acceleration (a).
f = ma

a. solve this equation for a.

b. if the force is f = –25 units and the mass is m = 10 units, find the acceleration, a.

c. if the force is f = 25 units and the acceleration is a = 5 units, find the mass, m.