The sum is (100x28A + 9B)/100x9B and its numerator is 28A9B . For the rest have a look at ry1.
Let the original length of the wire be 1 . Then , 1 + 2/3 + 4/3 + 6/3 + 8/3 + 10/3 + 12/3 + 14/3 + 16/3 + 18/3 + ...
1+2+4+6 + (2+4+8+10+14+16)/3 = 13+18 is the result of first 9 additions .
2 + 2/3 + 2/5 = ? .
2+1+2+3 +1/4 + 2/4 + 3/4 + 2/3 + 5/6 = 8 + 3/2 + 4/6 + 5/6 = 8+3/2+3/2 = ? .
It should be around a half due to 3rd term .
7/15 + 9/15 + 2/25 + 1/14 + 8/14 = 1 1/15 + 2/25 + 9/14 = 1 + 5/75 + 6/75 + 9/14 = 1 + 11/75 + 9/14 = .
Have please a look at ry1 .
Just set A=1 and B=2 and try .
From first brine : 6 g. water, 4 g salt ; from second 7 g water, 3 g salt and from 3rd : 24 g water, 6 g salt. A total of 50 g. brine containing ...
1/3 rd of the sum 1/20 + 1/15 + 1/12 gives 1/15 and this result is not correct.
In a minute a total of 20+15+12=47 toys are produced and the average time of production is 3/47 minutes.
Look at the numbers and just guess, you need to be quick .
(1000+300+90+27)/2000 = 1417/2000 .
Have a look at ry1 . Just to get acquainted with set theory .
Try it with the simplest possible common denominator 100. 70 passed math. 40 passed physics 12 of which have already been taken into account. 2 failed
with a total of 100.
437/35+943/105+3/5 + 144/7+19/42+61/21 = (1311+943+63)/105 + (864+19+122)/42 = 2317/105 + 1005/42 = ... (LCM = 210) It should be something around 45 !
You may not know division of fractions, just find the hours spent in sleep and then get a quarter of it .
(1+7/9+5/9)x63 will be the price of all three. So,(1+7/9+5/9)x21=?
Without having a look at ry1, try to force the upper and lower fractions to have a common denominator AxA .
The last two are around 1 whereas the first two are around a half .
7+8+43/5+9+9=?
5/(A+5) < 1/2 .
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