What Does Standard Algorithm Mean

The Standard Multiplication Algorithm

This is a complete lesson with explanations and exercises about the standard algorithm of multiplication (multiplying in columns), meant for fourth grade. First, the lesson explains (step-past-stride) how to multiply a 2-digit number past a single-digit number, and then has exercises on that. Next, the lesson shows how to multiply how to multiply a three or 4-digit number, and has lots of exercises on that. there are also many discussion issues to solve.

The standard algorithm of multiplication is based on the principle that you already know: multiplying in parts (partial products): merely multiply ones and tens separately, and add.

However, in the standard fashion the calculation is done at the same time every bit multiplying. The calculation looks more compact and takes less space than the "piece of cake way to multiply" you take learned.

The standard way to multiply

"The easy style"

1 half dozen 3 × 4 ii	1 6 iii × 4 2 5 2
Multiply the ones: 4 × three = 12 Identify ii in the ones place, only write the tens digit (ane) higher up the tens cavalcade as a piffling retentivity note. You are regrouping (or conveying).	Then multiply the tens, calculation the i ten that regrouped. 4 × 6 + 1 = 25 Write 25 in front end of the ii. Annotation that 25 tens means 250!

half dozen three
× four

1 2
+ 2 iv 0

2 5 two

In the "like shooting fish in a barrel way," we multiply in parts, and the calculation is done separately.

The standard way to multiply

"The easy way"

3 seven 5 × 7 five	3 7 5 × 7 five ii 5
Multiply the ones: 7 × 5 = 35 Regroup the 3 tens.	Multiply & add the tens: 7 × 7 + 3 = 52

7 five
× 7

3 five
+ 4 9 0

5 2 5

i. Multiply using both methods: the standard one and the easy one.

two. Multiply using both methods: the standard 1 and the easy ane.

3. Multiply. Exist careful with the regrouping.

4. Solve. Too, write number sentences (additions, subtractions, multiplications) on the empty lines.

a. What is the cost of buying three chairs for $48 each?

_________________________________________________

And the toll for six chairs? ____________________________

b. You earn $77 a 24-hour interval. How many days practice you demand to work
in order to accept $600 or more? Guess and check.

_________________________________________________

With a 3- or four-digit number you accept to regroup many times.

3
2 3 8
× 4

2

ane 3
2 3 8
× 4

5 2

ane 3
two iii 8
× 4

nine v ii

Multiply the ones starting time.

4 × 8 = 32

Write 2 in the ones
place and regroup
the 3 tens to the
tens column.

And so multiply the tens,
calculation the 3 regrouped
tens.

4 × 3 + 3 = 15

Write 5 in the tens place
and regroup the 1 hundred.

Then multiply the hundreds,
calculation the regrouped
hundred.

4 × ii + 1 = 9

Write 9 in the hundreds place.

1
7 six 5 ii
× 5

0

2 1
7 6 v two
× 5

half-dozen 0

3 2 ane
7 6 five ii
× 5

2 six 0

three 2 1
vii 6 5 2
× 5

3 eight ii 6 0

Multiply the ones:

5 × 2 = 10

Write 0 in the ones
identify and regroup
the ane ten.

Then the tens. Add
the regrouped ten:

5 × 5 + 1 = 26

Write 6 in the tens
place and regroup
the ii hundreds.

Multiply the
hundreds.

5 × 6 + 2 = 32

Write 2 in the
hundreds place,
and regroup the
3 thousands.

Multiply the thousands:

5 × 7 + 3 = 38

Write 38 in front of
the 260.

5. Multiply using both methods: the standard i and the easy one.

half-dozen. Multiply using the standard method.

seven. Solve the word problems. Also, write number sentences (additions, subtractions,
multiplications) to bear witness what you calculate.

a. The school has 304 students. To go to
the museum, they hired buses which can
each seat 43 passengers. How many buses
did they need?
Hint: Estimate and check.

b. The schoolhouse also has 24 teachers. How many
seats were left empty in those buses when all
the students and all the teachers joined the trip?

This old video of mine below as well too explains how to teach the multiplication algorithm. At showtime, the video goes through the partial products algorithm (multiplying in parts), and and so explains the standard multiplication algorith (as in the lesson on this folio).