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PLS HURRY HAVE 10MIN. LEFT
the unit digit of a 2 digit number is 5 more than the tens diget and the number itself is 3 times the sum of the digits. find the NUM

Respuesta :

mhanifa

Answer:

  • 27

Step-by-step explanation:

Let the tenth digit is x and units digit is y.

We have the following equations:

  • y = x + 5
  • (x + y)*3 = 10x + y

Simplify the second equation:

  • 3x + 3y = 10x + y
  • 2y = 7x

Solve by substitution:

  • 2(x + 5) = 7x
  • 2x + 10 = 7x
  • 7x - 2x = 10
  • 5x = 10
  • x = 2

Find y:

  • y = 2 + 5
  • y = 7

The number is 27

Here the equations are if the digits be a and b

  • b=a+5--(1)

3(a+b)=10a+b

  • 3a+3b=10a+b
  • 7a=2b
  • b=7/2a--(2)

Equate both

  • 7a/2=a+5

  • 7a=2a+10
  • 5a=10
  • a=2

And

  • b=2+5=7

The number is 27

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