Find all natural numbers having two digit , knowing that twice the units digit 1 more than the ten digit , and if we write that two digits in reverse order, we get a new number which is 27 less than the old one
Suppose \(\overline{ab}\) is a 2 digit number with the property that the 6 digit number \(\overline{1234ab}\) is divisible by 9 and \(\overline{ab1234}\) is divisible by 11. What is a2 - b2
Find the digit of the number unit (15+2)2002
Alice is playing with words. At each tick of her grandfather’s clock she swaps two letters. What is the smallest number of clock ticks during which she can change WORDS to SWORD?(A) 3 (B) 4 (C) 6 (D) 7 (E) 8
This pinwheel star is formed by rotating a right-angled triangle
around one of its corners. What is the angle at each of the nine
tips that are marked with dots?
(A) 30◦
(B) 40◦
(C) 45◦
(D) 50◦
(E) 60◦
I have twelve paint tins each capable of holding twelve litres. Half of them are half
full. A third of them are a third full. The rest are one-sixth full. How many litres of
paint do I have in total?
(A) 48 (B) 50 (C) 52 (D) 54 (E) 56
The average of three numbers is 42. All three are whole positive number and are different from each other.
If the least number is 20, what could be the greatest possible number of the remaining two numbers?
Answer: ......
the sum of the digits of a certain two - digits number is 11. when you reverse its digits you decrease the number by 9
Three children: Mark, Tom, Andy ate 23 cookies altogether. Tom ate more cookies than Andy, Mark. What is the smallest possible number of cookies that Tom ate?
Find the value of n such that \(A=n^3-2n^2+2n-4\) is a prime number. The value of n is...
Given that A=1^n+2^n+.....+98^n, where n is an odd possitive number. Fine the remainder in the division of A by 5
