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Finding the Fourth Proportional to 378.90, 571.15 and 347.70

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Solution

The fourth proportional to 378.90, 571.15 and 347.70 is: 524.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.90 : 571.15 = 347.70 : x
  2. Step 2: Convert to fraction form
    378.90/571.15 = 347.70/x
  3. Step 3: Cross multiply
    378.90x = 571.15 × 347.70
  4. Step 4: Simplify right side
    378.90x = 198,588.86
  5. Step 5: Solve for x
    x = 198,588.86/378.90
  6. Step 6: Final answer
    x = 524.12

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.