Makahanap ng mabilis at maaasahang mga solusyon sa iyong mga problema sa IDNStudy.com. Sumali sa aming platform ng tanong at sagot upang makatanggap ng mabilis at eksaktong tugon mula sa mga propesyonal sa iba't ibang larangan.

the sum of the digits of a number of three digits is 14, the ten's digit being 4 more than the unit's digit. if 99 is subtracted from the number, the digits will be reversed. find the number.

Sagot :

Well, it looks like this will really take a very long time to solve. So, I think, I am going to make the linear equation of 2 variables write away. Let x be the units digit of the 3 digit number:

Equation:
      
    1.) 
      a.) y + 10 ( x + 4 ) + x = 14
      b.) { [ 100y + 10 ( x + 4 ) + x ] - 99 } = y + 10 ( x + 4 ) + 100x
   
     a.) y + ( x + 4 ) + x = 14
         y + x + 4 + x = 14
         y + 2x + 4 = 14
         y + 2x = 14 - 4
         y + 2x = 10
          y + 2x - 10 = 0
           2x - 10 = -y
           [tex] \frac{2x}{-1} - \frac{10}{-1} = \frac{-y}{-1} [/tex]
           -2x + 10 = y

b.) { [ 100 y + 10 ( x + 4 ) + x ] - 99 } = y + 10 ( x + 4 ) + 100x
    { [ 100y + 10x + 40 + x ] - 99 } = y + 10x + 40 + 100x
    [ ( 100 y + 11x + 40 ) - 99 ] = y + 110x + 40
    100y + 11x + 40 = y + 110x + 40 + 99
    100y + 11x + 40 = y + 110 x + 139
    100 ( - 2x + 10 ) + 11x + 40 = -2x + 10 + 110x + 139
    -200x + 1, 000 + 11x + 40 = 108x + 10 + 139
    -189x + 1, 040 = 108x + 149
    -189x + 1, 040 - 149 = 108x
    -189x + 891 = 108x
    891 = 108x + 189x
    891 = 297x
    [tex] \frac{891}{297} = \frac{297x}{297} [/tex]
     3  = x
    x = 3 = unit's digit
    x + 4 = 3 + 4 = 7 = ten's digit
    -2x + 10 = -2 ( 3 ) + 10 = -6 + 10 = 4 = y = hundred's digit

Hundred's digit = 4
Ten's digit = 7
Unit's digit = 3

Number formed = 473

Check: 
 
1.) Ten's digit is 4 more than the unit's digit:
 3 + 4 = 7
     7 = 7, CORRECT!!!

2.) The number formed - 99 = digits will be reversed:
  473 - 99 = 374
   473 and 374, REVERSED!!!, CORRECT!!!

Therefore, the answer is 473.