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Finding the Fourth Proportional to 505.80, 752.40 and 491.76

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Solution

The fourth proportional to 505.80, 752.40 and 491.76 is: 731.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.80 : 752.40 = 491.76 : x
  2. Step 2: Convert to fraction form
    505.80/752.40 = 491.76/x
  3. Step 3: Cross multiply
    505.80x = 752.40 × 491.76
  4. Step 4: Simplify right side
    505.80x = 370,000.22
  5. Step 5: Solve for x
    x = 370,000.22/505.80
  6. Step 6: Final answer
    x = 731.51

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.