5.3.b 5.3.c

Multiply & Divide Whole Numbers 5th Grade

Texas Essential Knowledge and Skills (TEKS): 5.3.b
multiply with fluency a three-digit number by a two-digit number using the standard algorithm;
Texas Essential Knowledge and Skills (TEKS): 5.3.c
solve with proficiency for quotients of up to a four-digit dividend by a two-digit divisor using strategies and the standard algorithm;

To multiply a two-digit number by a two-digit number, multiply
each digit in one of the numbers by each digit in the other number.

Example:

Step 1: Write the second number under the first number so that the corresponding places are lined up.

Step 2: Multiply the ones digit in the bottom number by the ones digit in the top number (9 × 8 = 72). Since 72 has two digits, both digits won't fit in the ones place. So, write the 9 in the ones place, and carry the 7 to the tens column.

Step 3: Multiply the ones digit in the bottom number by the tens digit in the top number (9 × 8 = 72). Then, add the 7 that was carried to the tens column in the previous step (72 + 7 = 79). Write the 9 in the tens place and the 7 in the hundreds place.

Step 4: Start a new line, and add a placeholder zero to the ones column. Then, multiply the tens digit in the bottom number by the ones digit in the top number (3 × 8 = 24).
Since 24 has two digits, both digits won't fit in the tens place. So, write the 4 in the tens place, and carry the 2 to the tens column.

Step 5: Multiply the tens digit in the bottom number by the tens digit in the top number (3 × 8 = 24). Then, add the 2 that was carried to the hundreds column (24 + 2 = 26). Write the 6 in the hundreds place and the 2 in the thousands place.

Step 6: Add to find the product (792 + 2,640 = 3,432).

Use long division to divide a multi-digit number by a one-digit number.

Example:

Step 1: Write the dividend under the long division symbol, and write the divisor to the left of the long division symbol.

Step 2: The first digit of the dividend, 3, is less than the divisor, 6, so divide the first two digits of the dividend by the divisor (32 ÷ 6 = 5 R2). Write the 5 in the hundreds place of the quotient.

Step 3: Bring down the next digit in the dividend, 1, and divide.
(21 ÷ 6 = 3 R3). Write the 3 in the tens place of the quotient.

Step 4: Bring down the next digit in the dividend, 3, and divide.
(33 ÷ 6 = 5 R3). Write the 5 in the ones place of the quotient.

Step 5: 3 cannot be divided by 6 evenly, so the 3 is the remainder. Write the remainder with the quotient.

Use long division to divide a multi-digit number by a two-digit number.

Example:

Step 1: Write the dividend under the long division symbol, and write the divisor to the left of the long division symbol.

Step 2: Divide the first two digits of the dividend by the divisor
(89 ÷ 19 = 4 R13).

Step 3: Bring down the next digit in the dividend, and divide
(133 ÷ 19 = 7).

Multiply & Divide Whole Numbers

Texas Essential Knowledge and Skills (TEKS): 5.3.b

multiply with fluency a three-digit number by a two-digit number using the standard algorithm;

Texas Essential Knowledge and Skills (TEKS): 5.3.c

solve with proficiency for quotients of up to a four-digit dividend by a two-digit divisor using strategies and the standard algorithm;

Processing Request...