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Finding the Fourth Proportional to 661.87, 987.95 and 613

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Solution

The fourth proportional to 661.87, 987.95 and 613 is: 915.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.87 : 987.95 = 613 : x
  2. Step 2: Convert to fraction form
    661.87/987.95 = 613/x
  3. Step 3: Cross multiply
    661.87x = 987.95 × 613
  4. Step 4: Simplify right side
    661.87x = 605,613.35
  5. Step 5: Solve for x
    x = 605,613.35/661.87
  6. Step 6: Final answer
    x = 915.00

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.