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Finding the Fourth Proportional to 646.02, 891.21 and 421.92

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Solution

The fourth proportional to 646.02, 891.21 and 421.92 is: 582.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.02 : 891.21 = 421.92 : x
  2. Step 2: Convert to fraction form
    646.02/891.21 = 421.92/x
  3. Step 3: Cross multiply
    646.02x = 891.21 × 421.92
  4. Step 4: Simplify right side
    646.02x = 376,019.32
  5. Step 5: Solve for x
    x = 376,019.32/646.02
  6. Step 6: Final answer
    x = 582.06

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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.