Mortar is made by mixing 4 parts sand to 1 part cement. A builder uses 100kg of sand.
How much cement must he use?
I thought it was 25kg, but I think thats wrong.
(sorry, this is probably really easy, but I'm rubbish at Maths)!!
2006-11-19 04:25:20 · 17 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Thank you all! Can you believe i'm nearly 28 and i still can't work out easy stuff like this!! And don't even get me started on Fractions..............!!!
2006-11-19 04:42:09 · update #1
add the parts together 4 + 1 = 5
divide the 100 by 5 = 20
therefore one part = 20
you need one part of cement = 20kg
i hope that helps
2006-11-19 05:10:47 · answer #1 · answered by Anonymous · 1⤊ 0⤋
no thats right. for each 1 of cement he needs 4 sand, so for 25 cement he needs 4 x 25 sand = 100
altogether he has 125 of mortar though 100 sand + 25 cement
2006-11-19 04:28:58 · answer #2 · answered by Anonymous · 1⤊ 0⤋
The Ratio of Cement to sand is dependant on what you are using the mix for, you should also consider a placticiser to stop your mortar cracking. Mix is best done by the shovel - 1 shovel load cement to three of sand - that way you won't mix up too much of the stuff and waste it.
2006-11-19 04:36:07 · answer #3 · answered by rusty b 2 · 0⤊ 2⤋
As far as I can tell 25Kg is correct... because 4 x 25 = 100.
2006-11-19 04:27:27 · answer #4 · answered by Robert W 5 · 1⤊ 0⤋
100kg is the 4 parts of salt and cement is 1 part. You would do 100kg/4 = 25kg.
You were right!
2006-11-19 04:29:47 · answer #5 · answered by Lee3319 2 · 1⤊ 0⤋
Your answer is correct 4 x 25 = 100
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For every 4 parts of sand 1 part of cement is used.
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2006-11-19 04:41:52 · answer #6 · answered by SAMUEL D 7 · 0⤊ 0⤋
25kg is the correct answer
4 parts sand = 100kg
therefore 1 part = 25kg
2006-11-19 04:38:49 · answer #7 · answered by Gunship 1 · 1⤊ 0⤋
100/4 =25
100 kg sand so need to find how much cement.
so for every 4 parts we need one cement
therefore 100sand divided by 4 parts will give us how much cement...are you following!!
therefore 25, as you rightly said, is the answer
2006-11-19 05:36:48 · answer #8 · answered by Kate J 4 · 0⤊ 0⤋
Yes, 25kg is correct!
2006-11-19 04:34:44 · answer #9 · answered by Angela B 1 · 1⤊ 0⤋
25 kg is one part
100 kg is the four parts(4*25=100)
i hope that this helps
2006-11-19 05:51:04 · answer #10 · answered by Anonymous · 0⤊ 0⤋