MULTIPLICATION OF MONEY

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Multiplication is the process of calculating the total of one number multiplied by another. Multiplying means repeated addition of a number. (The number must all be the same before we can use it to multiply). There is no special rule for multiplying money. Rules that apply to multiplication of numbers also apply to multiplication of money.

Examples

$7       1      2                              #2      1     9                                       #4        1      5

×                 3                             ×             6                                        ×                 5

$ 2   1      3      6                       #1   3    0     4                                  # 2   0     7      5

 

Word Problem on Multiplication of Money

1. A book costs $ 67. How much will be paid for 102 such books?

   Solution:

The cost of one book            = $ 6 7                   6 7

Number of books                  = 1 0 2             × 1 0 2

The cost of 102 books          = $ 67 × 102        1 3 4

= $ 6834         + 6 7 0 0

6 8 3 4

Therefore, cost of 102 books = $ 6834

2. A bicycle costs $ 215. How much will be paid for 87 such bicycles?

Solution: 

The cost of one bicycle            = $ 2 1 5                   2 1 5

Number of bicycle                    = 8 7                       × 8 7

The cost of 87 bicycles            = $ 2 1 5 × 8 7        1 5 0 5

= $ 6834            + 1 7 2 0 0

1 8 7 0 5

Therefore, cost of 87 bicycles = $ 18705

3. The monthly salary of a man is $ 2,625. What is his annual income by salary?
   Solution:

Monthly income               = $2,625                   2 6 2 5

Annual income                 = $2,625 × 12             × 1 2

= $31,500                 5 2 5 0

 + 2 6 2 5 0

   3 1 5 0 0

Therefore, annual income = $ 31,500

4. A chair costs $ 452 and a table costs $ 1750. What will be cost of 15 chairs and 30 tables?
   Solution:

(i) Cost of one chair         = $ 452

Cost of 15 chairs             = $ 452 × 15

= $ 6,780

(ii) Cost of one table        = $ 1,750

Cost of 30 tables             = $ 1,750 × 30

= $ 52,500

Therefore, cost of 15 chairs and 30 tables = $ 6,780 + $ 52,500

Quiz

1. A seed company filled 4 bags with seed. They put 2 grams of seed in each bag. How many grams of seed are there in all the bags combined?
2. A chair costs $ 542 and a table costs $ 750. What will be cost of 15 chairs and 30 tables?
3. The monthly salary of a Mrs. Loreta is $ 3,850. What is her annual income by salary?
4. A bicycle costs $ 425. How much will be paid for 87 such bicycles?

 

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