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Finding the Fourth Proportional to 637.21, 880.47 and 491.11

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Solution

The fourth proportional to 637.21, 880.47 and 491.11 is: 678.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.21 : 880.47 = 491.11 : x
  2. Step 2: Convert to fraction form
    637.21/880.47 = 491.11/x
  3. Step 3: Cross multiply
    637.21x = 880.47 × 491.11
  4. Step 4: Simplify right side
    637.21x = 432,407.62
  5. Step 5: Solve for x
    x = 432,407.62/637.21
  6. Step 6: Final answer
    x = 678.60

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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.