Exercise :: Ratio and Proportion  General Questions
 Ratio and Proportion  Important Formulas
 Ratio and Proportion  General Questions
11.  The salaries A, B, C are in the ratio 2 : 3 : 5. If the increments of 15%, 10% and 20% are allowed respectively in their salaries, then what will be new ratio of their salaries? 

Answer: Option C Explanation: Let A = 2k, B = 3k and C = 5k.

12.  If 40% of a number is equal to twothird of another number, what is the ratio of first number to the second number? 

Answer: Option C Explanation:
A : B = 5 : 3. 
13.  The fourth proportional to 5, 8, 15 is: 

Answer: Option B Explanation: Let the fourth proportional to 5, 8, 15 be x. Then, 5 : 8 : 15 : x 5x = (8 x 15)

14.  Two number are in the ratio 3 : 5. If 9 is subtracted from each, the new numbers are in the ratio 12 : 23. The smaller number is: 

Answer: Option B Explanation: Let the numbers be 3x and 5x.
23(3x  9) = 12(5x  9) 9x = 99 x = 11. The smaller number = (3 x 11) = 33. 
15.  In a bag, there are coins of 25 p, 10 p and 5 p in the ratio of 1 : 2 : 3. If there is Rs. 30 in all, how many 5 p coins are there? 

Answer: Option C Explanation: Let the number of 25 p, 10 p and 5 p coins be x, 2x, 3x respectively.
Hence, the number of 5 p coins = (3 x 50) = 150. 