Have please a look at ry1 .
Just set A=1 and B=2. You now have 1212/120 - 2121/210. Write it in the form 1200/120 + 12/120 - (2100/210 + 21/210) .
For all 3 working : In a minute a total of 20+15+12=47 toys are produced and the average time of production is 3/47 minutes.
For M 1 and M2 working : In a minute a total of 20+15=35 toys are produced and the average time of production is 2/35 minutes. So the question is 3/47 - 2/35 = ?
Look at the numbers and just guess, you need to be quick .
(1000-300+90-27)/2000 = .../2000 .
In 24 hours 1 , ..., 10,11,12,13,14,15,16,17,18,19,.,21 have 1 in display . Fraction is: 12/24
24 hours are 24x60 = 1440 minutes. 01,...,10,11,12,13,14,15,16,17,18,19,.,21,...,31, ...,41,...,51. The fraction is 15/60.
437/35-943/105-3/5 + 144/7-19/42+61/21 = 61/21 + 144/7-19/42+61/21 = 61/21 + 967/42 = ... It should be something around 45 !
In one hour the first pipe fils it , the second empties a half; a half remains full .
21 + 2/3 should be 2/3 rds of ...
The best method to deal in a hurry to substitute the answers. The second is to go in the reverse order .
She hat at the end 7. One extra she gave to her 3rd friend means 8 is the half of remainings after 2nd. To 2nd she gave extra 2 means she had 27 after
first friend. 3 extra to first means she had 30 after she gave 1/4 ths.
The last is greater than 1 .
7-8+8+3/5-9+9=?
It should be 5/(A-5) > 3/2 . For A = 5, 6, 7 and 8 the inequality is valid. In case A=5 no fraction is obtained.
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