SOLUTION: a number of two digits is 9 more than 5 times the sum of its digits. its ten's digit is one more that its unit's digit. find the number.
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-> SOLUTION: a number of two digits is 9 more than 5 times the sum of its digits. its ten's digit is one more that its unit's digit. find the number.
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You can put this solution on YOUR website! let a = the 10's digit
let b = the units
Then
10a+b = the two digit number
:
a number of two digits is 9 more than 5 times the sum of its digits.
10a + b = 5(a + b) + 9
10a + b = 5a + 5b + 9
10a - 5a = 5b - b + 9
5a = 4b + 9
:
its ten's digit is one more that its unit's digit.
a = b + 1
:
Replace a with (b+1) in the the eq: 5a = 4b + 9
5(b+1) = 4b + 9
5b + 5 = 4b + 9
5b - 4b = 9 - 5
b = 4
:
I'll let you find a, check the obtained number in the 1st statement so see if it is true
