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Finding the Fourth Proportional to 878.90, 1,315 and 545.40

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Solution

The fourth proportional to 878.90, 1,315 and 545.40 is: 816.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    878.90 : 1,315 = 545.40 : x
  2. Step 2: Convert to fraction form
    878.90/1,315 = 545.40/x
  3. Step 3: Cross multiply
    878.90x = 1,315 × 545.40
  4. Step 4: Simplify right side
    878.90x = 717,201
  5. Step 5: Solve for x
    x = 717,201/878.90
  6. Step 6: Final answer
    x = 816.02

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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.