Which Number is the odd one out?

A) 7145
B) 2716
C) 5321
D) 4135

Can you count the number of triangles in the given figure?

Solve this logical number series puzzle by replacing the question mark with the correct number
9090 = 4
1234 = 0
6055 = 2
9081 = 4
8888 = ?

If,
9 * 8 * 7 = 65
8 * 7 * 6 = 50
7 * 6 * 5 = 37

Find
6 * 5 * 4 = ?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What does the below rebus puzzle mean?

Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?

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

Can you find the number?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.