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Finding the Fourth Proportional to 987.05, 1,362.11 and 637.74

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Solution

The fourth proportional to 987.05, 1,362.11 and 637.74 is: 880.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    987.05 : 1,362.11 = 637.74 : x
  2. Step 2: Convert to fraction form
    987.05/1,362.11 = 637.74/x
  3. Step 3: Cross multiply
    987.05x = 1,362.11 × 637.74
  4. Step 4: Simplify right side
    987.05x = 868,668.84
  5. Step 5: Solve for x
    x = 868,668.84/987.05
  6. Step 6: Final answer
    x = 880.07

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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.