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How do you work out 37.5 divided by 25 without a calculator

lydiafoof

Hi,

Could someone please show me a method without using a calculator

Thanks :smile:

Reply 1

Doctor_Einstein

Original post by lydiafoof

Hi,

Could someone please show me a method without using a calculator

Thanks :smile:

You want to calculate 37.5/25.

My first step would be divide both sides by 5 to give:

7.5/5

Then 7.5/5 is easily evaluated to give 1.5

Reply 2

callum_law

1*25=25
0.5*25=12.5
25+12.5=37.5

Reply 3

miser

Dividing by 25 upfront is tricky, but you can express the problem in an easier way.

Dividing by 25 is the same as dividing by 100, then multiplying by 4, since 25 goes into 100 4 times. Dividing by 100 is very easy.

37.5 / 100 = 0.375

Multiplying 0.375 is tricky upfront as well, but 2 goes into 4 2 times, so you can times by 2 twice. Doubling a number is also very easy.

0.375 * 2 = 0.75
0.75 * 2 = 1.5

Therefore 3.75 / 25 = 1.5

Reply 4

ztibor

Original post by lydiafoof

Hi,

Could someone please show me a method without using a calculator

Thanks :smile:

I would do the followings:

As 25=100/4 so dividing by 25 means multiplying by 4 and dividing by 100.

1. 37.5 *4 = 30*4 + 7.5*4=120+30=150
2. Divide this by 100

Reply 5

Drusilla

Original post by lydiafoof

Hi,

Could someone please show me a method without using a calculator

Thanks :smile:

25 goes into 37.5 once, so note down 1. Remainder is 12.5.
25 doesn't go into 12.5, so put a decimal point after the 1 you noted down, which now allows you to multiply the remainder by 10, which is 125.

25 goes into 125 five times, so put a 5 after the decimal point. Remainder is zero, so the answer is complete. It's 1.5.

Long division / bus shelter method.