standard_description: Apply properties of operations as strategies to multiply and divide. (Students need not use formal terms for these properties.) ^( )Examples: If 6 × 4 = 24 is known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5 + 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
problem_activity: Problem 1
Randomly select a digit 0–9 (by using a ten-sided die, a spinner, or a random number generator). Whatever number it lands on, enter the digit in one of the eight spots below. After eight turns, the board becomes an addition problem with two 4-digit numbers to add together. The goal is to place the numbers in strategic places to get the highest sum without going over 10,000.
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Problem 2
Estimate. Then solve.
a.
$$\begin{align} 207,426 \\ {+ \ 128,744}& \\ \hline \end{align}$$
b.   252, 393 =
$$\square$$
− 747,607
c.
$$k$$
= 94,989 + 619,732 + 4,506
Problem 3
Tom Brady has 66,159 career passing yards. Peyton Manning, the all-time leading quarterback with the most career passing yards, has 5,781 more passing yards than Tom Brady does. How many passing yards does Peyton Manning have?


aligns: no