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Finding the Fourth Proportional to 661.31, 912.72 and 377.72

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Solution

The fourth proportional to 661.31, 912.72 and 377.72 is: 521.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.31 : 912.72 = 377.72 : x
  2. Step 2: Convert to fraction form
    661.31/912.72 = 377.72/x
  3. Step 3: Cross multiply
    661.31x = 912.72 × 377.72
  4. Step 4: Simplify right side
    661.31x = 344,752.60
  5. Step 5: Solve for x
    x = 344,752.60/661.31
  6. Step 6: Final answer
    x = 521.32

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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.