Home / 1,590.38-2,385.30-420.40

Finding the Fourth Proportional to 1,590.38, 2,385.30 and 420.40

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Solution

The fourth proportional to 1,590.38, 2,385.30 and 420.40 is: 630.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,590.38 : 2,385.30 = 420.40 : x
  2. Step 2: Convert to fraction form
    1,590.38/2,385.30 = 420.40/x
  3. Step 3: Cross multiply
    1,590.38x = 2,385.30 × 420.40
  4. Step 4: Simplify right side
    1,590.38x = 1,002,775.73
  5. Step 5: Solve for x
    x = 1,002,775.73/1,590.38
  6. Step 6: Final answer
    x = 630.52

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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.