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Finding the Fourth Proportional to 647.58, 970.72 and 339.78

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Solution

The fourth proportional to 647.58, 970.72 and 339.78 is: 509.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.58 : 970.72 = 339.78 : x
  2. Step 2: Convert to fraction form
    647.58/970.72 = 339.78/x
  3. Step 3: Cross multiply
    647.58x = 970.72 × 339.78
  4. Step 4: Simplify right side
    647.58x = 329,831.24
  5. Step 5: Solve for x
    x = 329,831.24/647.58
  6. Step 6: Final answer
    x = 509.33

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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.