help with fractions
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help with fractions
Hello, please could anybody help me with this: calculate 3/8 of 980. I'm sure it's very simple but i'm no good and i'm hoping I can show your reply to dd.
this is year 6 homework and I think it may be a sats type of question as the sheet is from the LA assessment team
many thanks
b
this is year 6 homework and I think it may be a sats type of question as the sheet is from the LA assessment team
many thanks
b
Calculate 3/8 of 980
Divide 980 by 8 = 122.5
Multiply by 3 = 367.5
or
Multiply 980 by 3 = 2940
Divide by 8 = 367.5
Remind her that fraction questions are division sums when concerning the denominator (bottom number), and multiplying sums when concerning the numerator(top number), or in this case a bit of both!
Divide 980 by 8 = 122.5
Multiply by 3 = 367.5
or
Multiply 980 by 3 = 2940
Divide by 8 = 367.5
Remind her that fraction questions are division sums when concerning the denominator (bottom number), and multiplying sums when concerning the numerator(top number), or in this case a bit of both!
Hi
When you see "of" in a fraction sum, this means "times", so 3/8 of 980 means 3/8 x 980.
An alternative method for multiplication of fractions is to reduce the numbers down.
3/8 x 980
The 8 and 980 can be halved, giving
3/4 x 490
The 4 and 490 can be halved, giving
3/2 x 245
The top line in a fraction are multiplied giving,
3 x 245 = 735
and this is divided by the number in the bottom line giving,
735 divided by 2 = 367.5
Here is another example of cancelling down fractions:
8/9 x 15/32
You cancel down any top number with any bottom number
8 and 32 can be cancelled, by halving, to 4 and 16, then 2 and 8, then 1 and 4, giving
1/9 x 15/4
9 and 15 can be cancelled down, by dividing by 3, to 3 and 5, giving
1/3 x 5/4
Multiply top line, then bottom line gives the answer,
5/12
Regards
Mike
When you see "of" in a fraction sum, this means "times", so 3/8 of 980 means 3/8 x 980.
An alternative method for multiplication of fractions is to reduce the numbers down.
3/8 x 980
The 8 and 980 can be halved, giving
3/4 x 490
The 4 and 490 can be halved, giving
3/2 x 245
The top line in a fraction are multiplied giving,
3 x 245 = 735
and this is divided by the number in the bottom line giving,
735 divided by 2 = 367.5
Here is another example of cancelling down fractions:
8/9 x 15/32
You cancel down any top number with any bottom number
8 and 32 can be cancelled, by halving, to 4 and 16, then 2 and 8, then 1 and 4, giving
1/9 x 15/4
9 and 15 can be cancelled down, by dividing by 3, to 3 and 5, giving
1/3 x 5/4
Multiply top line, then bottom line gives the answer,
5/12
Regards
Mike