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Finding the Fourth Proportional to 647.20, 970.80 and 355.60

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Solution

The fourth proportional to 647.20, 970.80 and 355.60 is: 533.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.20 : 970.80 = 355.60 : x
  2. Step 2: Convert to fraction form
    647.20/970.80 = 355.60/x
  3. Step 3: Cross multiply
    647.20x = 970.80 × 355.60
  4. Step 4: Simplify right side
    647.20x = 345,216.48
  5. Step 5: Solve for x
    x = 345,216.48/647.20
  6. Step 6: Final answer
    x = 533.40

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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.