Dividing numbers with a remainder
Sometimes when we divide two numbers we can get a remainder.
There are different ways of representing the answer to a division question that has a remainder.
First, though, let鈥檚 start by looking at the idea that for every fraction there is a decimal that has the same value
For example, we could say that 陆 is equivalent to 0.5 or that one tenth is equivalent to 0.1.
Example 1
Take a look at this equation below. Is it true or false?
This is incorrect!
Two fifths can also be written as four tenths so the answer should be 0.4.
Any fraction can be changed into an equivalent decimal by dividing the numerator by the denominator.So, with the fraction two fifths, we would divide 2 by 5.
That sounds a bit 鈥榳eird鈥 because you might think that 5 cannot go into 2 鈥 but it can!
Example 2
Twenty three is NOT a multiple of six, so we will know that the answer will not be a whole number (integer).
Three different pupils respond with whiteboards:
The first two answers are correct but the third answer is wrong 鈥 why?
This is another example of a recurring decimal.
We can just write:
(with the dot above the digit three only).
The answer would be 3.83 (rounded to two decimal places).
Example 3
Let鈥檚 change one ninth into an equivalent decimal!
So one ninth is equivalent to zero point one recurring.
Could you write down the decimal equivalent two ninths? What about two thirds?
Two ninths = 2 x one ninth = 2 x 0.111 鈥 = 0.222 鈥 or zero point two recurring.
Two thirds = six ninths = 6 x one ninth = 6 x 0.111 鈥 = 0.666 鈥 or zero point six recurring.
Example 4
Fatima and six of her friends agree to share the cost of some party food they have bought to celebrate a special occasion!
The total cost of the food is 拢45
Fatima is correct when she says that this means they each need to pay just over 拢6.42 each 鈥 in fact 拢6.43 would be JUST OK!
We could even check this out:
Activity
Quiz
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