SSC CGL 20201)If 3A = 4B = 5C, then A : B : C is equal to :
20 : 15 : 12
let 3A = 4B = 5C = K
\(A= {K \over 3}, B= {K \over 4}, C= {K \over 5}\)
\(A:B:C = {K \over 3} : {K \over 4}: {K \over 5}\)
\(= {1 \over 3} : {1 \over 4}: {1 \over 5}\)
=20:15:12
SSC CGL 20202)If an amount of Rs.990 is divided among A, B and C in the ratio of 3 : 4 : 2, then B will get :
Rs. 440
Ratio of the A, B and C = 3 : 4 : 2;
Amount = 990;
Share of B = \(\frac{4}{3 + 4 + 2} \times 990 = \frac{4}{9} \times 990\) = Rs.440
SSC CGL 20203)The total number of students in a class is 65. If the total number of girls in the class is 35, then the ratio of the total number of boys to the total number of girls is:
6 : 7
The total number of students = 65; Total number of girls = 35; Total number of boys = 65 - 35 = 30; Required ratio = 30 : 35 = 6 : 7
SSC CGL 20204)If A : B = 3 : 5, and B : C = 2 : 3, then A : B : C is equal to:
6 : 10 : 15
A : B = 3 : 5 = 6 : 10; B : C = 2 : 3 = 2 x 5 : 3 x 5 = 10 : 15; A : B : C = 6 : 10 : 15
SSC CGL 20205)In wallet, there are notes of the denominations ₹10 and ₹50. The total number of notes is 12. The number of ₹10 and 50 notes are in the ratio of 1 : 2. Total money in the wallet is:
₹ 440
The ratio of the number of ₹10 and ₹50 notes = 1 : 2;
The total number of notes = 12;
The number of ₹10 notes = \(\frac{1}{1 + 2} \times 12 = 4\);
Money from the ₹10 notes = 4 x 10 = Rs.40;
The number of ₹50 notes = 12 - 4 = 8;
Money from the ₹50 notes = 8 x 50 = Rs.400;
Total money in the wallet = 40 + 400 = Rs.440
SSC CGL 20206)A certain amount is divided among Sunita, Amit and Vibha in the ratio of 2 : 3 : 4. If Vibha gets Rs. 14,416, then the total amount is:
Rs. 32,436
Ratio of the amount of Sunita, Amit and Vibha = 2 : 3 : 4;
Let the amount of Sunita, Amit and Vibha be 2x, 3x and 4x.
Amount of Vibha = 14416;
4x = 14416;
x = 14416/4 = 3604;
Total amount = 2x + 3x + 4x = 9x = 9 x 3604 = Rs.32436
SSC CGL 20207)The ratio of the ages of A and B, 8 years ago, was 2 : 3. Four years ago, the ratio of their ages was 5 : 7. What will be the ratio of their ages 8 years from now?
4 : 5
8 years ago the ratio of the ages of A and B = 2 : 3 ;
Let the 8 years ago ages of A and B be 2x and 3x respectively.
4 years age of A = 2x + 4 ; 4 years agoof B = 3x + 4 ;
Four years ago,the ratio of their ages = 5 : 7 ;
\({2x+4\over3x+4}= {5\over7}\) ; ⇒ 14x + 28 = 15x + 20; ⇒ x = 8 ;
8 years from now, Age of A = 2x + 16 = 2 x 8 + 16 = 32;
8 years from now, Age of B = 3x + 16 = 3 x 8 + 16 = 40;
Ratio of their ages 8 years from now = 32 : 40 = 4 : 5