Home / 1,298.28-1,947.24-420.87

Finding the Fourth Proportional to 1,298.28, 1,947.24 and 420.87

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Solution

The fourth proportional to 1,298.28, 1,947.24 and 420.87 is: 631.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,298.28 : 1,947.24 = 420.87 : x
  2. Step 2: Convert to fraction form
    1,298.28/1,947.24 = 420.87/x
  3. Step 3: Cross multiply
    1,298.28x = 1,947.24 × 420.87
  4. Step 4: Simplify right side
    1,298.28x = 819,534.90
  5. Step 5: Solve for x
    x = 819,534.90/1,298.28
  6. Step 6: Final answer
    x = 631.25

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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.