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Two numbers are in the ratio 4:9, If the mean proportional between them is 24, Find. the positive difference between the two numbers.

A30

B25

C15

D20

Answer:

D. 20

Read Explanation:

Two numbers are in the ratio 4 : 9.
Let the numbers be 4k and 9k.

The mean proportional (geometric mean) between them is given as 24.


(4k)(9k)=24\sqrt{(4k)(9k)} = 24

36k2=24\sqrt{36k^2} = 24

6k=24k=46k = 24 \Rightarrow k = 4

So, the two numbers are:

  • (4k = 16)

  • (9k = 36)

Positive difference between the two numbers:


3616=2036 - 16 = \boxed{20}

Answer: 20


Related Questions:

The mean proportion of number 0.049 and 0.9 is:
11 : 132 = 22 : ____
3 വർഷം മുമ്പ്, രാജുവിന്റെയും ദീപക്കിന്റെയും പ്രായം യഥാക്രമം 5 : 9 ആയിരുന്നു. 5 വർഷത്തിനുശേഷം, ഈ അനുപാതം 3 : 5 ആയി മാറും. രാജുവിന്റെ ഇപ്പോഴത്തെ പ്രായം കണ്ടെത്തുക.
Devi and Deva started the business with the investment in the ratio of 12:7 and the ratio of the investment period of Devi and Deva is x:6. At the end of the business, the profit share of Devi is Rs.1300 less than Deva and the total profit of the business is Rs.16900, then find the value of x?
a:b=2:5, b:c= 4:3 ആയാൽ a:b:c എത്ര