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Finding the Fourth Proportional to 663.54, 915.70 and 380

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Solution

The fourth proportional to 663.54, 915.70 and 380 is: 524.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.54 : 915.70 = 380 : x
  2. Step 2: Convert to fraction form
    663.54/915.70 = 380/x
  3. Step 3: Cross multiply
    663.54x = 915.70 × 380
  4. Step 4: Simplify right side
    663.54x = 347,964.10
  5. Step 5: Solve for x
    x = 347,964.10/663.54
  6. Step 6: Final answer
    x = 524.41

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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.