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Finding the Fourth Proportional to 646.29, 891.83 and 380.75

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Solution

The fourth proportional to 646.29, 891.83 and 380.75 is: 525.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.29 : 891.83 = 380.75 : x
  2. Step 2: Convert to fraction form
    646.29/891.83 = 380.75/x
  3. Step 3: Cross multiply
    646.29x = 891.83 × 380.75
  4. Step 4: Simplify right side
    646.29x = 339,557.91
  5. Step 5: Solve for x
    x = 339,557.91/646.29
  6. Step 6: Final answer
    x = 525.40

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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.