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Finding the Fourth Proportional to 387, 534.10 and 221.25

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Solution

The fourth proportional to 387, 534.10 and 221.25 is: 305.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    387 : 534.10 = 221.25 : x
  2. Step 2: Convert to fraction form
    387/534.10 = 221.25/x
  3. Step 3: Cross multiply
    387x = 534.10 × 221.25
  4. Step 4: Simplify right side
    387x = 118,169.63
  5. Step 5: Solve for x
    x = 118,169.63/387
  6. Step 6: Final answer
    x = 305.35

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.