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Finding the Fourth Proportional to 616.50, 851.98 and 505.80

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Solution

The fourth proportional to 616.50, 851.98 and 505.80 is: 699.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    616.50 : 851.98 = 505.80 : x
  2. Step 2: Convert to fraction form
    616.50/851.98 = 505.80/x
  3. Step 3: Cross multiply
    616.50x = 851.98 × 505.80
  4. Step 4: Simplify right side
    616.50x = 430,931.48
  5. Step 5: Solve for x
    x = 430,931.48/616.50
  6. Step 6: Final answer
    x = 699.00

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.