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Finding the Fourth Proportional to 505.08, 699.80 and 497.21

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Solution

The fourth proportional to 505.08, 699.80 and 497.21 is: 688.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.08 : 699.80 = 497.21 : x
  2. Step 2: Convert to fraction form
    505.08/699.80 = 497.21/x
  3. Step 3: Cross multiply
    505.08x = 699.80 × 497.21
  4. Step 4: Simplify right side
    505.08x = 347,941.57
  5. Step 5: Solve for x
    x = 347,941.57/505.08
  6. Step 6: Final answer
    x = 688.88

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.