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Finding the Fourth Proportional to 661.71, 913.12 and 378.14

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Solution

The fourth proportional to 661.71, 913.12 and 378.14 is: 521.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.71 : 913.12 = 378.14 : x
  2. Step 2: Convert to fraction form
    661.71/913.12 = 378.14/x
  3. Step 3: Cross multiply
    661.71x = 913.12 × 378.14
  4. Step 4: Simplify right side
    661.71x = 345,281.69
  5. Step 5: Solve for x
    x = 345,281.69/661.71
  6. Step 6: Final answer
    x = 521.80

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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.