Which two signs need to be interchanged to make the following equation correct?
45 – 9 ÷ 3 +5 ×6 =32

A father is 5 times as old as his son. His son is 6 years old. His son is 6 years old. After how many years, will the father be 4 times as old as his son?

If "÷" denotes "multiplied by", "+" denotes "subtracted from", "x" denotes "added to" and "–" denotes "divided by",then
12 – 6 + 28 × 3 ÷ 9 = ?

In the following question, two signs and two numbers need to be interchanged to make it correct. Select the appropriate signs and number from the given alternatives.
6 × 8 + 2 = 20

Select the set in which the number are related in the same way as are the number of the following set.
( 11, 16, 20)

If two is subtracted from each odd digit and three is added to each even digit in the number 3675249 how many digits will appear twice in the new number thus formed?