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Finding the Fourth Proportional to 645.90, 891.31 and 366.12

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Solution

The fourth proportional to 645.90, 891.31 and 366.12 is: 505.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.90 : 891.31 = 366.12 : x
  2. Step 2: Convert to fraction form
    645.90/891.31 = 366.12/x
  3. Step 3: Cross multiply
    645.90x = 891.31 × 366.12
  4. Step 4: Simplify right side
    645.90x = 326,326.42
  5. Step 5: Solve for x
    x = 326,326.42/645.90
  6. Step 6: Final answer
    x = 505.23

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.