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Finding the Fourth Proportional to 647.64, 971.55 and 214.75

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Solution

The fourth proportional to 647.64, 971.55 and 214.75 is: 322.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.64 : 971.55 = 214.75 : x
  2. Step 2: Convert to fraction form
    647.64/971.55 = 214.75/x
  3. Step 3: Cross multiply
    647.64x = 971.55 × 214.75
  4. Step 4: Simplify right side
    647.64x = 208,640.36
  5. Step 5: Solve for x
    x = 208,640.36/647.64
  6. Step 6: Final answer
    x = 322.15

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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.