In a two-digit number, the digit in the unit’s place is four times the digit in ten’s place and sum of the digits is equal to 10. What is the number? Choices:
A) 14  B) 41  C) 41  D) None of these  E) Cannot be determined
Solution   Let the ten's digits be x. Then, unit's digit = 4x.   ∴ x + 4x = 10 ⇔ 5x = 10 ⇔ x = 2.   So, ten's digit = 2, unit's digit = 8.   Hence, the required number is 28.   Answer None of these
<result>D</result>
In a two-digit number, the digit in the unit’s place is four times the digit in ten’s place and sum of the digits is equal to 10. What is the number?