Question
Two-third of two-fifth of three-fourth of a number is 36. What is the square root of four-fifth of that number?
- 9
- 12
- 14
- 16
Hint:
We are given that 2/3 * 2/5 * 3/4 * x = 36. We will simplify the given expression and find the value of x. Then we will find the value of √(4/5 * x)
The correct answer is: 12
GIVEN-
2/3 of 2/5 of 3/4 of a number = 36
TO FIND-
√(4/5 of the number)
SOLUTION-
Let the given number be x.
∴ 2/3 * 2/5 * 3/4 * x = 36
∴ (2 * 2 * 3) / (3 * 5 * 4) * x = 36
∴ 12/60 * x = 36
∴ 1/5 * x = 36
∴ x = 36 * 5 .................................... (Multiplying both sides by 5)
∴ x = 180 ........................................ (Equation i)
We need to find-
√(4/5 * x)
= √(4/5 * 180) ....................... (From Equation i)
= √(4/5 * 180)
= √144
= 12
FINAL ANSWER-
Option 'a' i.e. '12' is the correct answer to the given question.
Related Questions to study
Students of a class collected as many paise from each student of class as is the number of students in that class. If the total collection is Rs. 59.29, then find the total number of students in the class.
Students of a class collected as many paise from each student of class as is the number of students in that class. If the total collection is Rs. 59.29, then find the total number of students in the class.
The cube root of .000216 is
The cube root of .000216 is
What is the smallest number by which 3600 be divided to make it a perfect cube?
What is the smallest number by which 3600 be divided to make it a perfect cube?
The largest four-digit number, which is a perfect cube, is:
The largest four-digit number, which is a perfect cube, is:
The least number that should be multiplied with 1008 to make it a perfect square is
Alternatively, the question can be solved by multiply numbers in each of the options given and then check whether the resultant number is a perfect square or not-
a. 5
1008 * 5 = 5040
We know that 5040 is not a perfect square because √5040 = 12√35.
b. 2
1008 * 2 = 2016
We know that 2016 is not a perfect square because √2016 = 12√14.
c. 7
1008 * 7 = 7056
We know that 7056 is a perfect square because √7056 = 84.
d. 8
1008 * 8 = 8064
We know that 8064 is not a perfect square because √8064 = 24√14.
FINAL ANSWER REMAINS THE SAME.
The least number that should be multiplied with 1008 to make it a perfect square is
Alternatively, the question can be solved by multiply numbers in each of the options given and then check whether the resultant number is a perfect square or not-
a. 5
1008 * 5 = 5040
We know that 5040 is not a perfect square because √5040 = 12√35.
b. 2
1008 * 2 = 2016
We know that 2016 is not a perfect square because √2016 = 12√14.
c. 7
1008 * 7 = 7056
We know that 7056 is a perfect square because √7056 = 84.
d. 8
1008 * 8 = 8064
We know that 8064 is not a perfect square because √8064 = 24√14.
FINAL ANSWER REMAINS THE SAME.