The difference between the digits of a two-digit number is 3. If the d...
Let the unit’s digit be x.
Ten’s digit = x + 3.Original number =10(x + 3) + 1(x)
= 10x + 30 + x
= 11x + 30
After interchange, resulting number
= 10 (x) + 1 (x + 3)
= 10x + x + 3
= 11x + 3
∴ 11x + 3 + 11x + 30 = 143
⇒ 22x + 33 = 143
⇒ 22x = 143 – 33
⇒ 22x = 110
⇒
Original number = 11x + 3 = 11 × 5 + 3
= 55 + 3 = 58
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The difference between the digits of a two-digit number is 3. If the d...
**Problem Analysis:**
Let's assume the original two-digit number is xy, where x represents the tens digit and y represents the units digit. According to the given information, the difference between the digits is 3. This can be written as:
x - y = 3 ---(1)
When the digits are interchanged, the resulting number is yx. If this number is added to the original number xy, we get 143. Mathematically, this can be represented as:
xy + yx = 143 ---(2)
We need to find the original number xy.
**Solution:**
To solve this problem, we can use a systematic approach. Let's consider all the possible values for x and y and check if they satisfy both equations (1) and (2).
Let's start with the possible value of x. Since x represents the tens digit, it can only take values from 1 to 9 (excluding 0).
Case 1: x = 1
If x = 1, then y = 1 + 3 = 4 (from equation 1).
The original number xy = 14.
Interchanging the digits, we get yx = 41.
Adding the original number and the interchanged number, we get 14 + 41 = 55, which is not equal to 143.
Case 2: x = 2
If x = 2, then y = 2 + 3 = 5 (from equation 1).
The original number xy = 25.
Interchanging the digits, we get yx = 52.
Adding the original number and the interchanged number, we get 25 + 52 = 77, which is not equal to 143.
Case 3: x = 3
If x = 3, then y = 3 + 3 = 6 (from equation 1).
The original number xy = 36.
Interchanging the digits, we get yx = 63.
Adding the original number and the interchanged number, we get 36 + 63 = 99, which is not equal to 143.
Case 4: x = 4
If x = 4, then y = 4 + 3 = 7 (from equation 1).
The original number xy = 47.
Interchanging the digits, we get yx = 74.
Adding the original number and the interchanged number, we get 47 + 74 = 121, which is not equal to 143.
Case 5: x = 5
If x = 5, then y = 5 + 3 = 8 (from equation 1).
The original number xy = 58.
Interchanging the digits, we get yx = 85.
Adding the original number and the interchanged number, we get 58 + 85 = 143, which is equal to 143.
Therefore, the original number is 58, which matches option A.
The difference between the digits of a two-digit number is 3. If the d...
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