A. 1
B. 2
C. 3
D. 4
E. None of these
Explanation:
Let the two-digit number be 10a + b
a = b + 2 — (1)
10a + b = 7(a + b) => a = 2b
Substituting a = 2b in equation (1), we get
2b = b + 2 => b = 2
Hence the units digit is: 2.
Related Mcqs:
- In a three digit number, the hundred digit is 2 more than the tens digit and the units digit is 2 less than the tens digit. If the sum of the digits is 18, find the number?
A. 975
B. 753
C. 642
D. 684
E. None of these - The number obtained by interchanging the two digits of a two-digit number is less than the original number by 45. If the sum of the two digits of the number so obtained is 13, then what is the original number?
A. 49
B. 94
C. 83
D. Either (a) or (b)
E. None of these - The sum of the digits of a two-digit number is 12. The difference of the digits is 6. Find the number?
A. 93
B. 39
C. 75
D. 48
E. Either (a) or (b) - If the number obtained on interchanging the digits of a two-digit number is 18 more than the original number and the sum of the digits is 8, then what is the original number ?
A. 26
B. 35
C. 53
D. Cannot be determined - How many four digit numbers can be formed using the digits {1, 3, 4, 5, 7,9}(repetition of digits is not allowed)?
A. 360
B. 60
C. 300
D. 180 - A two-digit number is such that the product of the digits is 8. When 18 is added to the number, then the digits are reversed. The number is :_________?
A. 18
B. 24
C. 42
D. 81 - A man invests a certain sum of money at 6% per annum simple interest and another sum at 7% per annum simple interest. His income from interest after 2 years was Rs. 354. One-forth of the first sum is equal to one-fifth of the second sum. The total sum invested was :
A. Rs.3100
B. Rs.2700
C. Rs.2200
D. Rs.1800 - The average of the two-digit numbers, which remain the same when the digits interchange their positions, is__________?
A. 33
B. 44
C. 55
D. 66 - How many four digit even numbers can be formed using the digits {2, 3, 5, 1, 7, 9}
A. 60
B. 360
C. 120
D. 240 - The sum of the squares of three numbers is 138, while the sum of their products taken two at a time is 131. Their sum is :___________?
A. 20
B. 30
C. 40
D. None of these
