Home / 1,298.80-1,948.12-519.20

Finding the Fourth Proportional to 1,298.80, 1,948.12 and 519.20

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Solution

The fourth proportional to 1,298.80, 1,948.12 and 519.20 is: 778.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,298.80 : 1,948.12 = 519.20 : x
  2. Step 2: Convert to fraction form
    1,298.80/1,948.12 = 519.20/x
  3. Step 3: Cross multiply
    1,298.80x = 1,948.12 × 519.20
  4. Step 4: Simplify right side
    1,298.80x = 1,011,463.90
  5. Step 5: Solve for x
    x = 1,011,463.90/1,298.80
  6. Step 6: Final answer
    x = 778.77

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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.