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Finding the Fourth Proportional to 813.69, 1,221 and 351.93

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Solution

The fourth proportional to 813.69, 1,221 and 351.93 is: 528.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.69 : 1,221 = 351.93 : x
  2. Step 2: Convert to fraction form
    813.69/1,221 = 351.93/x
  3. Step 3: Cross multiply
    813.69x = 1,221 × 351.93
  4. Step 4: Simplify right side
    813.69x = 429,706.53
  5. Step 5: Solve for x
    x = 429,706.53/813.69
  6. Step 6: Final answer
    x = 528.10

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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.