What is the ratio of elephants to monkeys in a national zoo, if number

Question

What is the ratio of elephants to monkeys in a zoo, if number of elephants is less than 20?

(1) Monkeys are 20 more than elephants in number.

(2) Number of elephants is a factor of 20, and more than 5.

pushpitkc · Answer

Let the number of elephants be E and number of monkeys be M

Given data:   E < 20

We need to find out the ratio  \frac{E}{M} 
1. M = E + 20
Case 1: E = 2, M = 22, Ratio is 11:1
Case 2: E = 4, M = 24, Ratio is 6:1  (Insufficient)

2. E is a factor of 20 and E > 5
E could take values of 10. but without any information about M, 
we cannot find the ratio  (Insufficient)

Combining the information present in the statements, 
E = 10 and M = 30 and we have a ratio  \frac{E}{M} = \frac{1}{3}   (Sufficient - Option C)

EgmatQuantExpert · Answer

Solution

Given:  
 • Number of elephants in the zoo is less than 20

To find:  
 • The ratio of elephants to monkeys in the zoo

Analysing Statement 1  
 • As per the information given in statement 1, monkeys are 20 more than elephants in number
 o From this statement, we cannot find out the number of elephants
o Hence, we also cannot find out the number of monkey and the ratio of elephants and monkeys

Hence, statement 1 is not sufficient to answer

Analysing Statement 2  
 • As per the information given in statement 2, number of elephants is a factor of 20, and more than 5
• We know, more than 5 there are only 2 factors of 20 = 10 and 20
 o However, we also know that number of elephants are less than 20 
• Therefore, we can conclude that number of elephants is 10
 o But from this information, we cannot find the number of monkeys

Hence, statement 2 is not sufficient to answer

Combining Both Statements  
Taking the information from both the statements, we can say:
 • Number of elephants = 10
• Number of monkeys = 10 + 20  
Therefore, we can find out the ratio of elephants to monkeys in the zoo

Hence, the correct answer is option C.

Answer: C

What is the ratio of elephants to monkeys in a national zoo, if number

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