If '+' means minus, '-' means multiplication, '÷' means plus, and 'x' means division, then solve the equation: 
15 - 3 + 10 x 5 ÷ 5

If 'x' means 'addition', '-' means 'division', '/' means 'subtraction' and '+' means 'multiplication', then which of the equation is correct?

If '+' stands for multiplication, '-' stands for addition, 'x' stands for division, then what is the value of 128 + 9 - 16 x 4 = ?

If 'x' means addition, '-' means division, '÷' means subtraction and '+' means multiplication, then which of the equations is correct?

If 4 x 5 x 2 = 524, 3 x 7 x 2 = 723, and 6 x 8 x 7 = 876, then 9 x 4 x 5 = ?

Some equations have been solved on the basis of a certain system. Find the correct answer for the unsolved equation on that basis. If 98-39-27=31, 87-38-34-20 =? and 79-25-12 = ?

If '+' means '=', '-' means 'x', '*' means '+' and 'x' means '-', then 36x12+4+6-2-3= ?

What will come in the place of ‘?’ in the following equation, if ‘÷’ and ‘–‘ are interchanged and ‘×’ and ‘+’ are interchanged?

15 × 9 + 7 ÷ 26 – 13 = ?

Select the set, from the given options, in which the numbers are related in the same way as are the numbers of the following sets.

(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g. 13 – Operations on 13 such as adding/subtracting/multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

(6, 13, 78)

(5, 22, 110)

If + means -, - means ×, × means ÷, ÷ means +, then what will come in place of the question mark (?) in the following equation?

28 - 6 ÷ 4 + 14 × 14 = ?

In the following number-pairs, the second number is obtained by applying certain mathematical operations to the first number. Which numbers should replace X and Y so that the pattern followed by the two numbers on the left side of :: is the same as that on the right side of :: ?

(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g. 13 Operations on 13 such as adding/subtracting /multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

X : 649 :: 956 : Y

Which two numbers should be interchanged to make the given equation correct?

75 ÷ 5 + 15 × 4 - 17 × 3 + (60 ÷ 6) × 10 = 100

(Note: Interchange should be done of the entire number and not individual digits of a given number.)