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Finding the Fourth Proportional to 818.50, 1,227.54 and 509.21

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Solution

The fourth proportional to 818.50, 1,227.54 and 509.21 is: 763.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.50 : 1,227.54 = 509.21 : x
  2. Step 2: Convert to fraction form
    818.50/1,227.54 = 509.21/x
  3. Step 3: Cross multiply
    818.50x = 1,227.54 × 509.21
  4. Step 4: Simplify right side
    818.50x = 625,075.64
  5. Step 5: Solve for x
    x = 625,075.64/818.50
  6. Step 6: Final answer
    x = 763.68

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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.