Find Number of Brother, sister and friends

Tell Brothers, Sisters and Friend of anyone

This puzzle will let you know the number of brothers, sisters and close friends your friend do have through a recreational mathematical puzzle. Are you ready to play this game with your friends? This game is based on mathematical calculation so please don’t use calculator or any electronic device as it will ruin the purpose of the game. Mathematical games are the best exercise for your brain so keep doing the calculation in your head or do manual calculation.

Before I come to the game let me advise you to be alert while playing this game with your near and dear ones. Take a piece of paper and pen and give it to your friend or someone with whom you want to play this game. I am sure at the end of this game you are definitely going to get a good response from the audience.

Here comes the steps which you will dictate and your friend will follow.

• Ask your friend to write the number of his/ her sister on a piece of paper and multiply it by 2.
• Add 3 to that total.
• Now multiply the result by 5 and add the number of brothers to this number.
• Further multiply this number by 10 and add the number of your close friends to it.
• I think you are OK with the calculation. In order to tell you the correct answer I will finally ask you to add 125 to the result and tell me the final answer.
• I have to blow the whistle this time by giving you the correct answer. Wait let me subtract 275 from your final result and come to the answer.
• You will have a 3 digit number at the end of the game. The number at the hundred place tells you the number of sisters and the number places at ten’s digit is the number of brother and the unit digit tells you the number of good friends you have.

Isn’t it a funny and mind blowing game?

Example: - Suppose you have 3 sisters, 2 brothers and 4 close friends. Let’s begin the calculation to check how effective this game is.
• Number of sister × 2 = 3 × 2 = 6
• Add 3 to it = 6 + 3 = 9
• Multiply it by 5 = 9 × 5 = 45
• Add number of brothers to it = 45 + 2 = 47
• Multiply the result by 10 = 47 × 10 = 470
• Add number of close friends to it = 470 + 4 = 474
• Add 125 to it and tell me the result = 474 + 125 = 599
• Finally I shall subtract 275 from your result = 599 – 275 = 324

Now the question is – Why this puzzle works?

A three digits number with its digits X, Y and Z = 100X + 10Y + Z
• Multiply Number of sister (X) by 2 = X × 2 = 2X
• Add 3 to it = 2X + 3 = 2X + 3
• Multiply it by 5 = (2X + 3)× 5 = 10X + 15
• Add number of brothers (Y) to it = 10X + 15 + Y
• Multiply the result by 10 = (10X + 15 + Y)× 10 = 100X + 10Y + 150
• Add number of close friends (Z) to it = 100X + 10Y + 150+ Z
• Add 125 to it and tell me the result = 100X + 10Y + 150+Z + 125
• Finally I shall subtract 275 from your result = 100X + 10Y + Z+ 275 – 275 = 100X + 10Y + Z

The three digit number with X at hundred place, Y at the Ten’s place and Z at the unit place = 100X + 10Y + Z

Dr Rajesh Kumar Thakur