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Finding the Fourth Proportional to 978.80, 1,465.77 and 545.05

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Solution

The fourth proportional to 978.80, 1,465.77 and 545.05 is: 816.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    978.80 : 1,465.77 = 545.05 : x
  2. Step 2: Convert to fraction form
    978.80/1,465.77 = 545.05/x
  3. Step 3: Cross multiply
    978.80x = 1,465.77 × 545.05
  4. Step 4: Simplify right side
    978.80x = 798,917.94
  5. Step 5: Solve for x
    x = 798,917.94/978.80
  6. Step 6: Final answer
    x = 816.22

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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.