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It has to be HCF of 420 and 130 which is 10

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Y-0.3X=0.75Y

Y-0.75Y=0.3X

X/Y=0.25/0.3=5/6

Thus the ratio is 5:6

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Suppose average age is A and age of Asha is X

Average age after the replacement of Asha by another woman is (7A-25+X)/7

According to question

(7A-25+X)/7=A+5

7A-25+x=7A+35

X=35+25=60

Ans 60

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Supposing a number has appeared on dice 1.

The probability of same number appearing on dice 2 is 1/6

Similarly, probability of same number appearing on dice 3 is 1/6

Thus, the probability of same number appearing on dice 2 & dice 3 together is 1/6*1/6=1/36

Ans 1/36

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Suppose amount invested is Rs 100 and rate of interest is R

According to question

(100*R*4)/100*1.5=(100*R*6)/100

i.e. R*4*1.5=R*6

i.e. R*6=R*6

which is true for all values of R.

Thus there is no unique value of R. 

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Suppose sped of car1 is 2X then speed of second car is 3X

and suppose car1 has travelled distance 3Y then car2 has travelled  distance 7Y

If T1 is time taken by car 1 then T1=3Y/2X

Similarly, if time taken by car2 is T2 then T2= 7Y/3X

Ttherefore, T1/T2= (3Y/2X)/(7Y/3X)= (3Y*3X)/(2X*7Y)=9/14

The ratio is 9:14

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If Satish takes 18 days then Biren can do it in 9 days

Therefore on each day Satish days 1/18 of work and Biren does 1/9 of work

I they work together, on each day they would day 1/18+1/9 i.e.3/118 or 1/6 of work.

Therefore, they will finish the work in 6 days

Ans 6 days

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Since we do not know the price & Consumption of Sugar this question can not be answered

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Total Sale price = 700*4.5+300*2.5=3900

Purchase price = 1000*3=3000

profit = Rs. 900

Average Profit = 900/1000=0.9 or 90 paisa