Happy fifth week of summer!
It sure does feel like summer now.
Figuring out the total cost when you're shopping, is a great application of mental math. Before we get back to multiplication, we're going to take a step back and review a simple mental math strategy for adding.
If I wanted to buy the Klondike Bars, a tub of Ben & Jerry's ice cream and some waffle cones, the total would be $3.98 + $3.98 + $2.98
$3.98 is $4.00 - 2 cents
$3.98 is $4.00 - 2 cents
$2.98 is $3.00 - 2 cents
$4.00 + $4.00 + $3.00 = $11.00
2 cents + 2 cents + 2 cents = 6 cents or $0.06 (in dollar notation)
So the total would be $11.00 - $0.06 (6 cents) = $10.94
Because we rounded up when we added, we have to subtract the difference between the actual cost of each item and the estimated cost (6 cents).
Try a few more using the items in the flyer.
