Re: BUSINESS MATHEMATICS

[rhiza]

[rhiza]

4. In multiplying a number by 5, move the decimal point 1 place to the right then divide by 2 since 5 is ½ of 10.

[rhiza]

5. In multiplying a number by 25, move the decimal point two places to the right, and divide it by number 4 since 25v is ¼ of 100

[rhiza]

6. In multiplying a number by 9; 99; 999…., move the decimal point as many nines in the multiplier to the right then subtract the multiplicand from the result.

[rhiza]

7. When multiplying the same numbers ending in 5, write 25 (5 x 5) as the last digits of the product, replace the remaining digit of the multiplicand by one greater than itself and multiply with the remaining digit in the multiplier, then affix to 25.

[rhiza]

8. Two numbers whose ending digits make a sum of 10 and whose remaining digits are the same. The ending digits will be multiplied and write the products as the last digits of the product. The remaining digits will be multiplied by one greater than itself.

[rhiza]

Checking
1. Multiply the numbers by applying commutative law.