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Finding the Fourth Proportional to 646.30, 891.88 and 397.63

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Solution

The fourth proportional to 646.30, 891.88 and 397.63 is: 548.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.30 : 891.88 = 397.63 : x
  2. Step 2: Convert to fraction form
    646.30/891.88 = 397.63/x
  3. Step 3: Cross multiply
    646.30x = 891.88 × 397.63
  4. Step 4: Simplify right side
    646.30x = 354,638.24
  5. Step 5: Solve for x
    x = 354,638.24/646.30
  6. Step 6: Final answer
    x = 548.72

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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.