Home / 1,078.20-1,618.50-429.39

Finding the Fourth Proportional to 1,078.20, 1,618.50 and 429.39

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Solution

The fourth proportional to 1,078.20, 1,618.50 and 429.39 is: 644.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,078.20 : 1,618.50 = 429.39 : x
  2. Step 2: Convert to fraction form
    1,078.20/1,618.50 = 429.39/x
  3. Step 3: Cross multiply
    1,078.20x = 1,618.50 × 429.39
  4. Step 4: Simplify right side
    1,078.20x = 694,967.72
  5. Step 5: Solve for x
    x = 694,967.72/1,078.20
  6. Step 6: Final answer
    x = 644.56

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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.