Mani is double the age of Prabhu , Ramona is half the age of Prabhu . If Mani is sixty years old , find out the age a Ramona . 

John ' s age is 42 years and Kelvin ' s age is 26 years and how many years ago was Kelvin ' s age half of John ' s age ? 

Out of 100 families in the neighbourhood, 50 members have radios , 75 members have TVs and 25 members have VCRs . Only 10 families have all three and each VCR owner also has a TV . If some families have radio only , how many have only TV ? 

In the following question, correct the equation by interchanging two numbers.
9 × 3 – 8 ÷ 2 + 7 = 26

If “P” denotes “divided by”, “R” denotes “added to”, “S” denotes “subtracted from” and “Q” denotes “multiplied by”, then
48 P 4 R 3 Q 4 S 6 Q 4 = ?

If “*” denotes “added to”, “&” denotes “divided by”, “@” denotes “multiplied by” and “%” denotes “subtracted from”, then
399 & 19 @ 21 % 41 * 100 =?

If “@” denotes “added to”, “#” denotes “multiplied by”, “®” denotes “divided by” and “%” denotes “subtracted from”, then which of the following equation is true?

The weights of 4 boxes are 30, 40, 50 and 80 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxes and in a combination a box can be used only once?