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Finding the Fourth Proportional to 620.65, 855.52 and 502.80

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Solution

The fourth proportional to 620.65, 855.52 and 502.80 is: 693.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.65 : 855.52 = 502.80 : x
  2. Step 2: Convert to fraction form
    620.65/855.52 = 502.80/x
  3. Step 3: Cross multiply
    620.65x = 855.52 × 502.80
  4. Step 4: Simplify right side
    620.65x = 430,155.46
  5. Step 5: Solve for x
    x = 430,155.46/620.65
  6. Step 6: Final answer
    x = 693.07

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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.