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Finding the Fourth Proportional to 647.44, 972.48 and 428.38

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Solution

The fourth proportional to 647.44, 972.48 and 428.38 is: 643.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.44 : 972.48 = 428.38 : x
  2. Step 2: Convert to fraction form
    647.44/972.48 = 428.38/x
  3. Step 3: Cross multiply
    647.44x = 972.48 × 428.38
  4. Step 4: Simplify right side
    647.44x = 416,590.98
  5. Step 5: Solve for x
    x = 416,590.98/647.44
  6. Step 6: Final answer
    x = 643.44

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.