1. 1000cm^3 of cement consists of 10% of granite . How much more granite must be added to make a mixture containing 70% of granite?
2. Jane ate 1/3 of pie and Terry ate of it . What fraction of the pie did they eat in all?
3. A potter took 8/9h to make a vase . How long would he tke to make 12vases if he took the same time to make each vase?
F.1數學一問;;有3題
2008-08-26 11:19 pm
回答 (2)
2008-08-26 11:51 pm
✔ 最佳答案
1.)1000cm^3 of cement consists of 10% of granite
That is 1000cm^3 of cement consists of 100cm^3 of granite
Let x cm^3 of granite have to be added to make a mixture containing of 70% granite
(100 + x) / (1000 + x) = 70%
100 + x = 0.7(1000 + x)
100 + x = 700 + 0.7x
0.3x = 600
x = 2000
therefore, 2000cm^3 of granite have to be added.
2.)
1 - 1/3 = 2/3
3.)
(8/9) x 12
= 32 / 3 hours
= 10 + (2/3) hours
2008-08-26 11:25 pm
Something (a fraction) has been missed in Question 2.
2. Jane ate 1/3 of pie and Terry ate (?????) of it . What fraction of the pie did they eat in all?
2. Jane ate 1/3 of pie and Terry ate (?????) of it . What fraction of the pie did they eat in all?
收錄日期: 2021-04-24 09:52:18
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