| 1. |
The sum of the first two digits of a three digit number is 4. The sum of the numbersthat is formed by using each digit of the number once is 1998. If the number has 8factors, then what is the number? |
|
Answer» The SUM of the first two digits of a three digit number is 4. The sum of the numbers that is formed by using each digit of the number once is 1998. The number has 8 factors. The number. Let the three digit number be ABC. A/q, a + b = 4 . . .(i) Again, the sum of the numbers which are by using each digit of the number once is 1998. According to the above given statement, we get :- Putting the places' value and adding further :- → 100a + 10b + c + 100a + 10c + b + 100B + 10a + c + 100b + 10c + a + 100c + 10a + b + 100c + 10b + a = 1998 → 200a + 200b + 200c + a + 10a + a + b + 10b + b + c + 10c + c = 1998 → 200a + 22a + 200b + 22b + 200c + 22c = 1998 → 222a + 222b + 222C = 1998 → a + b + c = 9 Putting the value of a + b from equation (i) :- 4 + c = 9 → c = 5 Possible values for a and b (c = 5): a = 1, b = 3 a = 2, b = 2 a = 3, b = 1 The required number could be :- 135, 225 or 315 A/q, the required number must have 8 factors. ◘ 135 is the only number which has 8 factors. So, a = 1 and b = 3. Again, putting the places' value and adding in abc :- abc = 100a + 10b + c → abc = 100(1) + 10(3) + 5 → abc = 100 + 30 + 5 → abc = 135 Hence, the answer is 135. |
|