Select the correct combination of mathematical signs to replace the * signs and balance the given equation.
 21 * 4 * 156 * 13 * 11 = 83

If the two signs, '+ and ÷ ' are interchanged, which of the following equations will be correct?

Select the correct combination of mathematical signs to sequentially replace the * signs and balance the given equation.
 65 * 45 * 25 * 5 * 35 * 60

Direction: Some equations have been solved on the basis of certain system. Find the correct answer for the unsolved equation on that basis.

2 × 4 × 6 = 4; 9 × 3 × 7 = 13; 4 × 7 × 6 = 3; 9 × 7 × 8 =?

In a certain language, if the signs + and ×, and the digits 3 and 8 are interchanged, then what is the value of the following expression?
 6 × 35 ÷ 5 + 8 – 9

Which of the following interchanges in signs and numbers will make the given equation correct?

8 x 9 + 2 = 74

Select the correct combination of mathematical signs to sequentially replace the # signs and to balance the given equation.
 [{(44 # 38) # (2 # 5)} # (4 # 2)] # 5 # 10

Which of the following symbols should be inserted in place of question mark (?) respectively (in the same order from left to right) in order to complete the given expression in such a manner that ‘U > S’, ‘Q < T’ and ‘S ≤ N’ definitely holds true?
 U > T ? D ≥ S ? Q ? N