If 21x = 79x, what is the value of x?

Replace the question mark with the correct number, given the pair of numbers exhibits a similar relationship?

? : 3839 :: 11 : 1209

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

What number divided by 4 is the same as that number minus 4?

There is a hypothetical state between the USA and Mexico border 'Tango'.
Here 70 percent of the population have defective eyesight, 75 percent are hard of hearing, 80 percent have Nose trouble and 85 percent suffer from allergies, what percentage (at a minimum) suffer from all four ailments?

Can you calculate the probability of getting a sum of six when a dice is thrown twice?

Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.

Can you solve below mathematical equation?

2^1234 - 2^1233

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?