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Decimal

Hello,

Can anyone explain how to calculate multiple using written method of 5.78 x4.3 please
Original post by Katarzyna1982
Hello,

Can anyone explain how to calculate multiple using written method of 5.78 x4.3 please

u basically multiply it w/o the decimals so 578 x 43 (the normal way) and u get 24854. and then u see how 5.78 has 2 decimal places and 4.3 has 1 decimal place so in total there r 3 decimal places so place the decimal point at 3dp making it 24.854
Reply 2
Original post by Katarzyna1982
Hello,

Can anyone explain how to calculate multiple using written method of 5.78 x4.3 please

if you mean "long multiplication" as we used to call it, then the above poster has essentially given you the method - treat it as a multiplication of whole numbers and then identify the correct position for the decimal point.

It is always good to do a simple "sanity check" on the answer as well - 5.78 lies between 5 and 6, and 4.3 lies between 4 and 5, so your answer should be a number between 20 and 30 - you shouldn't expect the final answer to be in the hundreds or less than 10 for example :smile:
Reply 3
Original post by j3ssica jon3s
u basically multiply it w/o the decimals so 578 x 43 (the normal way) and u get 24854. and then u see how 5.78 has 2 decimal places and 4.3 has 1 decimal place so in total there r 3 decimal places so place the decimal point at 3dp making it 24.854

Great thanks

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