Devon is buying 3 greeting cards that cost $0.97 each. how can rounding be used to estimate the total cost of the cards?
since each card is about $1, the total cost is approximately 3 + 1 = $4.
since each card is about $1, the total cost is approximately 3 x 1 = $3.
since he is buying about 10 cards, the total cost is approximately 10 x 0.97 - $9.70.
since he is buying about 10 cards, the total cost is approximately 10+ 0.97 = $10.97.

Ahigh definition tv cost $800 with a down payment of 2/5 of the cost. how much is left to pay, in dollars after the down payment has been made?

Meghan has created a diagram of her city with her house, school, store, and gym identified. a. how far is it from the gym to the store? b. meghan also wants to walk to get some exercise, rather than going to the gym. she decides to walk along arc ab. how far will she walk? round to 3 decimal places.

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?