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Finding the Fourth Proportional to 621.65, 931.95 and 485.30

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Solution

The fourth proportional to 621.65, 931.95 and 485.30 is: 727.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.65 : 931.95 = 485.30 : x
  2. Step 2: Convert to fraction form
    621.65/931.95 = 485.30/x
  3. Step 3: Cross multiply
    621.65x = 931.95 × 485.30
  4. Step 4: Simplify right side
    621.65x = 452,275.34
  5. Step 5: Solve for x
    x = 452,275.34/621.65
  6. Step 6: Final answer
    x = 727.54

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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.