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Finding the Fourth Proportional to 646.09, 891.54 and 397.42

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Solution

The fourth proportional to 646.09, 891.54 and 397.42 is: 548.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.09 : 891.54 = 397.42 : x
  2. Step 2: Convert to fraction form
    646.09/891.54 = 397.42/x
  3. Step 3: Cross multiply
    646.09x = 891.54 × 397.42
  4. Step 4: Simplify right side
    646.09x = 354,315.83
  5. Step 5: Solve for x
    x = 354,315.83/646.09
  6. Step 6: Final answer
    x = 548.40

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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.