Three numbers are in the ratio of 1:2:4. If 3 is added to the first and 8 is subtracted from the third, the new numbers will be the first and third terms of an A. P., whose second term is the second number. Find the original numbers.​

9514 1404 393

  5, 10, 20

Step-by-step explanation:

Suppose the three numbers are x, 2x, and 4x. Then they have the required ratios. After the transformation, we have ...

  ((x+3) +(4x -8))/2 = 2x . . . . . 2nd term is average of 1st and 3rd

  5x -5 = 4x   ⇒   x = 5

The original numbers are 5, 10, 20.

After the adjustment, the arithmetic sequence is 8, 10, 12.

the difference between a number and 5 is -2.

step-by-step explanation:

notice that the equation you are given has -2 (negative 2) on the right side, not 2. when you subtract 5 from a number n, you are finding the difference between the number and 5.

the difference between a number and 5 is -2.

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6