In 20 minutes, how many more times does a gerbil's heart beat than a rabbit's?

Animal	Heart rate (beats per minute)
Dog	100
Gertil	360
Rabbit	212

How many times does a dog's heart beat in 15 minutes?

Find the value of $x$.

$$x+100=100,000,000$$

Find product. Estimate to check that your answer is reasonable.

$$199 \times 99$$

Why is the standard form of $8^2$ NOT equal to $16 ?$

Three hundred fifty 10 -year-olds registered for a city-wide bowling tournament. If 205 participants are boys, how many are gurls?

Find product. Estimate to check that your answer is reasonable.

$$500 \times 62$$

How do you know if the actual product of $26 \times 44$ is between 800 and $1,500 ?$

Compare. Write $>,<$, or $=$ for each a $34,304 \bigcirc 43,403$ b $5.70 \bigcirc 5.7$ c $21,978 \bigcirc 21,789$

Camping Gear Prices

The club also needs to buy 16 dome tents and 16 propane stoves. Will they spend more or less on these items than on the backpacks? How much more or less?

write in standard form.

$$10 \times 10 \times 10 \times 10 \times 10$$

In Step 2 of Another Example, why is it necessary to regroup the $\mathbf{2 3}$ tens?

Estimate by using compatible numbers. Tell if your estimate is an overestimate or underestimate.

$$43 \times 27 \times 4$$

Four bags with 7 apples in each bag is the same amount as 7 bags with 4 apples in each bag. Which property of multiplication does this represent? A Associative B Commutative C Identity D Zero