Home / 1,515.80-2,272.08-638.78

Finding the Fourth Proportional to 1,515.80, 2,272.08 and 638.78

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Solution

The fourth proportional to 1,515.80, 2,272.08 and 638.78 is: 957.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,515.80 : 2,272.08 = 638.78 : x
  2. Step 2: Convert to fraction form
    1,515.80/2,272.08 = 638.78/x
  3. Step 3: Cross multiply
    1,515.80x = 2,272.08 × 638.78
  4. Step 4: Simplify right side
    1,515.80x = 1,451,359.26
  5. Step 5: Solve for x
    x = 1,451,359.26/1,515.80
  6. Step 6: Final answer
    x = 957.49

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.