Question

multiplication introduction
part 1 of 2
do these problems in your head. use paper only for the problems that you just cant do in your head. its important to do as many of these problems without paper as you can.
do not use a calculator at all.
7×10 =
59×10 =
100×82 =
30×3 =
90×6 =
40×5 =
4×700 =
70×900 =
50×200 =
check answers →
if you dont know to do the problem, just do your best. we will analyze your answers to give you personalized help.

Explanation:

Step1: Multiply by 10, add 0

$7 \times 10 = 70$

Step2: Multiply by 10, add 0

$59 \times 10 = 590$

Step3: Multiply by 100, add two 0s

$100 \times 82 = 8200$

Step4: Multiply 3×3, add one 0

$30 \times 3 = (3 \times 3) \times 10 = 90$

Step5: Multiply 9×6, add one 0

$90 \times 6 = (9 \times 6) \times 10 = 540$

Step6: Multiply 4×5, add one 0

$40 \times 5 = (4 \times 5) \times 10 = 200$

Step7: Multiply 4×7, add two 0s

$4 \times 700 = (4 \times 7) \times 100 = 2800$

Step8: Multiply 7×9, add three 0s

$70 \times 900 = (7 \times 9) \times 1000 = 63000$

Step9: Multiply 5×2, add three 0s

$50 \times 200 = (5 \times 2) \times 1000 = 10000$

Answer:

$7 \times 10 = 70$
$59 \times 10 = 590$
$100 \times 82 = 8200$
$30 \times 3 = 90$
$90 \times 6 = 540$
$40 \times 5 = 200$
$4 \times 700 = 2800$
$70 \times 900 = 63000$
$50 \times 200 = 10000$