Question

multiply two - digit numbers.

1. estimate:

87×91

1. estimate:

73×45
numbers by two - digit numbers
multiply three - digit numbers by two - digit numbers.

1. estimate:

Explanation:

Step1: Round 87 to 90

Round 87 to the nearest ten, which is 90.

Step2: Round 91 to 90

Round 91 to the nearest ten, which is 90.

Step3: Multiply the rounded numbers

$90\times90 = 8100$

Step4: For 73×45

Round 73 to 70.

Step5: Round 45 to 50

Round 45 to the nearest ten.

Step6: Multiply the rounded numbers

$70\times50=3500$

Answer:

1. Estimate: 8100
2. Estimate: 3500