Multiplication is the process t of the repetitive addition of any number ‘x’ for ‘n’ number of times, which we write as x * n. For Multiplying Whole Numbers And Decimals we proceed as follows:
a) Here we are multiplying two whole numbers.
b) We arrange the two numbers in two rows, by aligning from the right side and proceed for the multiplication
c) The top row is called the multiplicand and the bottom row is called the multiplier.
d) We pick the right most digit of the multiplier and multiply it with all the digits of the multiplicand.
e) In next step, we first write a zero on the ones place, pick the next right digit of the multiplier and then again multiply it with all the digits of the multiplicand.
f) We proceed in the same way till all the digits of the multiplier are multiplied by the multiplicand.
g) In next step we will add all rows, which we get after finding the product of the individual digits.
h) In the end we will count the number of places of digits on the right of the decimal and then place the decimal leaving the same number of digits in the sum so calculated.
i) Thus we get the product of a whole number with the decimal number.
For example, if we are multiplying 123 by 1.2, we write:
H T O
1 2 3
X 1 . 2
2 4 6
1 2 3 0
_____________
1 4 7 6
Now we observe that there exists only one digit after the decimal, so we say that the decimal will be placed leaving one digit from the right. Thus we can write
123 * 1.2 = 147.6.
In case we have two digits after the decimal then decimal will be placed leaving two digits from right.
This is all about multiplying whole numbers and decimals.