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Finding the Fourth Proportional to 646.80, 891.80 and 425.68

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Solution

The fourth proportional to 646.80, 891.80 and 425.68 is: 586.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.80 : 891.80 = 425.68 : x
  2. Step 2: Convert to fraction form
    646.80/891.80 = 425.68/x
  3. Step 3: Cross multiply
    646.80x = 891.80 × 425.68
  4. Step 4: Simplify right side
    646.80x = 379,621.42
  5. Step 5: Solve for x
    x = 379,621.42/646.80
  6. Step 6: Final answer
    x = 586.92

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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.