MENTAL MATH QUESTIONS
1. I am a two digit number above 50. The sum of my digits is 12. And the difference of my digits is 4.WHO AM I ?
2. I am a two digit number below 50.The sum of my digits is 13.And the product of my digits is 36.WHO AM I ?
3. I am a two digit number. The sum and the product of my digits are the same. WHO AM I ?
[ANSWER ALL THESE QUESTIONS WITH EXPLANATION(very important)]
Answers
Answer:
The Answer is 48
Step-by-step explanation:
Let x equal one of the digits. And let y equal the other digit.
You are told that the sum of the two digits is 12. So you can write an equation to express this as:
x + y = 12
Next you are told that the difference of the two digits is 4. In equation form this is:
x - y = 4
At this point you have a system of two independent equations that can be used to solve for the two unknowns.
x + y = 12
x - y = 4
If you add the two equations vertically, note that the +y and the -y will cancel each other and you are left with :
2 x = 16
Solve for x by dividing both sides by 2 to get x = 8
If one of the digits is 8 and the sum of the two digits is 12, then by subtraction you know that the other digit must be 4. So the two digits are 8 and 4.
From your answers for the digits you know that the answer formed from the two digits of 8 and 4 must be either 48 or 84. But you were told that the two-digit number you are looking for is less than 50. So the answer to this problem must be 48.
Hope this helps you.