Question
The sum of two numbers is 60 whereas the sum of their
reciprocals is (20/9). Find the square of the product of the two numbers.Solution
ATQ,
Let the two numbers be 'r' and 's'.
So, r + s = 60
And (1/r) + (1/s) = (20/9)
Or, {(r + s)/(rs)} = (20/9)
Or, rs = (9/20) × 60 = 27
So, required square = 27² = 729
- Find the number of possible digits 'm' such that the number 3816mn is divisible by 15.
A merchant bought 300 goods at Rs. 50 each. He sold a part at a 20% profit and the rest at a 10% loss. If his overall profit is 4%, how many goods did h...
If '63a9b' is a five-digit number which is divisible by 72, then find the value of (a + 2b).
- Out of his monthly income of Rs. 40000, Mohan spent Rs. 10000 less than he saved. What percentage of his income did he spend?
Find the sum of the first 20 natural numbers.
- The biggest three-digit number leaves 2 as a remainder when divided by 11, 9, and 4. What is the sum of its digits?
In a class of 40 students, 60% are boys and the rest are girls. If 50% of the boys and 70% of the girls passed the exam, how many students failed the exam?
When a number is increased by 30% then the number obtained is 34 less than thrice the original number. Find the original number.
Find the smallest integer greater than 100 which leaves remainder 4 when divided by each of 5, 6 and 7.
Find the sum of the first 45 natural numbers.