The sum of the digits of a two-digit number is 8. when the digits are reversed
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Let's call the original two digit number xy, where x is the tens digit and y is the ones digit. An algebraic representation of this number is 10x + y. Show The sum of the two digit number is 8: x+y=8 When the digits are reversed, the number increases by 36: (10y + x) - (10x + y) = 36
Now we have two equations and two unknown parameters, so we have enough information to find those parameters.
Solve for x: X=8-y
plug in x: (10y + 8-y) - (10(8-y)+ y) = 36
simplify: (9y + 8) - (80-9y) = 36 18y - 72 = 36 y = 108/18 = 6
so if y=6, then x=8-y=8-6=2
so our number is 26. 62 is 36 greater than 26, so everything checks out.
Upvote • 1 Downvote More Report  David W. answered • 11/09/17 Tutor 4.9 (106)I'll help you understand math! About this tutor › About this tutor › So, Sydney, interesting problem!
Let x be the first digit and y be the 2nd.
x + y = 8, right?
Now, in a two-digit number, the first digit is that digit times 10. 25 = 10(2) + 5, for example.
10y + x = 10x + y + 36. Make sense? Using algebra, we turn that into 9y - 9x = 36. We can divide all of that by 9 to get y - x = 4 What is the number the sum of two digits is 8?The sum of the digits of a two-digit numeral is 8. If the digits are reversed, the new number is 18 greater than the original number. How do you find the original numeral? So the number is 35!
How many twoanswer may be 17 , 26 35 , 44, 53 ,62 .......
Are two= 7 + 1 = 8, 71 - 54 = 17. answer is 71.
How many 2 digit numbers are there such that their square ends in 8?Answer. There are no any two digits number have their square ending with 8.
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