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Finding the Fourth Proportional to 647.18, 970.86 and 214.28

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Solution

The fourth proportional to 647.18, 970.86 and 214.28 is: 321.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.18 : 970.86 = 214.28 : x
  2. Step 2: Convert to fraction form
    647.18/970.86 = 214.28/x
  3. Step 3: Cross multiply
    647.18x = 970.86 × 214.28
  4. Step 4: Simplify right side
    647.18x = 208,035.88
  5. Step 5: Solve for x
    x = 208,035.88/647.18
  6. Step 6: Final answer
    x = 321.45

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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.