Example 9:
If 75 is divided into three parts proportional to 3, 5, 8, 9 then the smallest part is :
Answer :
ratio is = 3 : 5 : 8 : 9, sum of ratio terms is = 25.
So the smallest part is = ( 75 x 3 / 25 ) = 9 .
Example 10:
If A : B = 4 : 9 and B : C = 3 : 6 , then A : C is :
Answer : (A / B = 4 / 9, B / C = 3 / 6 )
= A / C = ( A /B x B / C) = ( 4 / 9 x 3 / 6 ) = 2 / 9 = A : C = 2 : 9.
Example 11 :
On dividing a sum of Rs 832 between Paul and john in the ratio 1 / 3 : 1 / 5 , their shares are
Answer :
So the given ratio is = 1 / 3 : 1 / 5 = 5 : 3
So , the 1st part = Rs ( 832 x 5 / 8 ) = Rs 520 , 2nd part = Rs ( 832 x 3 / 8 ) = Rs 312
So , their shares are : 520 and 312 .
Example 12 :
The Salary of Three friend A, B, C are divided into ratio 5 : 6 : 8.If the increment has given of 10%, 20%, 25%, Find the new ratio of three friend salary ?
Answer :
Step 1: We assume ration as 5x, 6x, 8x
now the increment of new salary is A = 110 / 100, B = 120 / 100, C = 125 / 100.
Step 2: A,s new salary is 110 X 5x / 100 = 55x / 10.
B,s new salary is 120 X 6x / 100 = 36x / 5.
C,s new salary is 125 X 8x / 100 = 10.
Step 3:New ratio is 55x / 10 : 36x / 5 : 10.
Example 13:
Rs 1210 were divided among three person P, Q, R so that P : Q = 5 : 4 and Q : R = 9 : 10. Then R gets the amount.
Answer :
P : Q = 5 : 4, Q : R = 9 : 10 = ( 9 x 4 / 9 ) : ( 10 x 4 / 9 ) = 4 : 40 / 9.
So, P : Q : R = 5 : 4 : 40 /9 = 45 : 36 : 40
Sum of ratio terms is = ( 45 + 36 + 40 ) =121.
R share of amount is Rs (1210 x 40 / 121) = Rs. 400 .
Example 14 :
Share Rs.4200 among joy, sanjay and bijoy in the ration 2 : 4 : 6.Find the amount received by sanjay.
Answer :
Amount received by sanjay.
4 / 12 X 4200 = 1400= ( related ratio / sum of ratio ) x Total amount
So, the Amount received by sanjay is 1400.
Example 15 :
Find the mean proportional between given two number that is 64 and 49.
Answer :
The mean proportion of two numbers is
Root of 64 and 49 is √8 x √ 7 = 8 x 7 = 56.
So, the mean proportional is 56.
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