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Finding the Fourth Proportional to 388, 535.20 and 310.56

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Solution

The fourth proportional to 388, 535.20 and 310.56 is: 428.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    388 : 535.20 = 310.56 : x
  2. Step 2: Convert to fraction form
    388/535.20 = 310.56/x
  3. Step 3: Cross multiply
    388x = 535.20 × 310.56
  4. Step 4: Simplify right side
    388x = 166,211.71
  5. Step 5: Solve for x
    x = 166,211.71/388
  6. Step 6: Final answer
    x = 428.38

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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.