Can you solve this tricky maths equation problem by replacing it? mark with the correct symbol?

19834 -----: 187
15921 -----: 153
17561 -----: 139
13734 -----: ???

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

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

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

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

In a stable, there are men and horses. In all, there are 22 heads and 72 feet. How many men and how many horses are in the stable