The sum of two numbers is twenty-one. One number is nineteen less than four times the other. Find the numbers.

9514 1404 393

  8, 13

Step-by-step explanation:

The given relationships can be put into two equations. Let x and y represent the numbers.

  x + y = 21 . . . . . their sum is 21

  y = 4x -19 . . . . .one is 19 less than 4 times the other

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Substituting for y in the first equation, we get ...

  x + (4x -19) = 21

  5x = 40 . . . . . . . . . add 19

  x = 8 . . . . . . . . . . . divide by 5

  y = 4(8) -19 = 13

The two numbers are 8 and 13.

15 and three-fifths miles

Step-by-step explanation:

First you add all the miles he rides.

Mon+Tue+Wed+Thu+Fri=84.4miles

Then you do 100m-84.4m=15.6