This is a problem from TOMATO Objective 01 based on worker and wages. This problem is helpful for ISI Entrance Exam. Try out the problem. (By Akash Singha Roy) Problem: TOMATO Objective 01 A worker suffers a $20 $ % cut in wages. He regains his original pay by obtaining a rise of (A) $20 […]
This is a problem from TOMATO Objective 94 based on number of divisors. This problem is helpful for ISI Entrance Exam. Try out the problem. (By Akash Singha Roy) Problem: TOMATO Objective 94 Number of divisors of $ 2700 $ Solution: $ 2700 = 2^2 \times 3^3\times 5^2 $ Hence, any divisor of $2700 $ […]
This is a problem from TOMATO Objective 21 based on positive integers. This problem is helpful for ISI Entrance Exam. Try out the problem. Problem: TOMATO Objective 21 Suppose x & y are positive integers, x>y, and 3x+4y & 2x+3y when divided by 5, leave remainders 2&3 respectively. It follows that when (x-y) is divided […]
This is a problem from Indian National Mathematics Olympiad, INMO, 2013 based on Orthocenter on perpendicular bisector. Try out this problem. Problem: Orthocenter on perpendicular bisector In an acute angled triangle ABC with AB < AC the circle $latex \Gamma $ touches AB at B and passes through C intersecting AC again at D. Prove […]
Find the number of 4-tuples (a,b,c,d) of natural numbers with $latex a \le b \le c $ and $latex a! + b! + c! = 3^d $ Discussion: Number of 4-tuples The basic idea is: factorial function is faster than the exponential function in the long run. Note that all three of a, b, c […]
Find the number of 8 digit numbers sum of whose digits is 4. Discussion: Suppose the number is $latex a_1 a_2 a_3 ... a_8 $.The possible values of $latex a_1 $ are 1, 2, 3, 4. We consider these four cases. If $latex a_1 = 4 $ then all other digits are 0 (since sum […]
In this post, there are questions from Regional Math Olympiad 2013. Try out the problems. Find the number of 8 digit numbers sum of whose digits are 4.Discussion Find the number of 4-tuples (a,b,c,d) of natural numbers with $latex a \le b \le c $ and $latex a! + b! + c! = 3^d […]
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