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Finding the Fourth Proportional to 620.55, 929.70 and 491.40

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Solution

The fourth proportional to 620.55, 929.70 and 491.40 is: 736.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.55 : 929.70 = 491.40 : x
  2. Step 2: Convert to fraction form
    620.55/929.70 = 491.40/x
  3. Step 3: Cross multiply
    620.55x = 929.70 × 491.40
  4. Step 4: Simplify right side
    620.55x = 456,854.58
  5. Step 5: Solve for x
    x = 456,854.58/620.55
  6. Step 6: Final answer
    x = 736.21

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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.