The sum of the digits of a two digits number is 10. If 18 be subtracte...
Problem Statement:
The sum of the digits of a two-digit number is 10. If 18 is subtracted from it, the digits in the resulting number will be equal. Find the number.
Solution:
Step 1: Understand the problem
We are given a two-digit number whose digits sum up to 10. When we subtract 18 from this number, the resulting number has equal digits. We need to find the original number.
Step 2: Let's assume the two-digit number
Let's assume the two-digit number as 'xy', where x represents the tens digit and y represents the units digit. So, the original number can be represented as 10x + y.
Step 3: Write the given conditions as equations
From the problem statement, we have two conditions:
1. The sum of the digits is 10: x + y = 10
2. The resulting number after subtracting 18 has equal digits: (10x + y) - 18 = yy
Step 4: Solve the equations
We have two equations with two unknowns. We can solve them simultaneously to find the values of x and y.
From equation 1, we can express x in terms of y: x = 10 - y
Substituting this value of x in equation 2, we get: (10 - y) + y - 18 = yy
Simplifying the equation, we get: 10 - 18 = yy - y
-8 = y(y - 1)
Step 5: Find the possible values of y
To find the possible values of y, we can factorize -8 and check for the values of y that satisfy the equation -8 = y(y - 1).
-8 can be factorized as (-4)(2) or (-2)(4) or (1)(-8)
For (-4)(2), we have:
y = -4, y - 1 = 2
y = 4, y - 1 = -2
For (-2)(4), we have:
y = -2, y - 1 = 4
y = 3, y - 1 = -4
For (1)(-8), we have:
y = 1, y - 1 = -8
y = 9, y - 1 = 0
Step 6: Check the valid values of y
Out of the possible values of y, we need to check which values satisfy the condition x + y = 10.
For y = 4, we have x = 10 - 4 = 6
For y = 3, we have x = 10 - 3 = 7
For y = 1, we have x = 10 - 1 = 9
Step 7: Final answer
From the above calculations, we find that the possible two-digit numbers satisfying the given conditions are 64, 73, and 91.
Therefore, the number can be 64 or 73 or 91.
The sum of the digits of a two digits number is 10. If 18 be subtracte...
It would've been easier with the options..because..u can try the given information on the option_
anyways
x+y=10
73 -18=55
and 7+3=10(by trial and error method...)
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