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Finding the Fourth Proportional to 661.69, 912.08 and 521.58

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Solution

The fourth proportional to 661.69, 912.08 and 521.58 is: 718.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.69 : 912.08 = 521.58 : x
  2. Step 2: Convert to fraction form
    661.69/912.08 = 521.58/x
  3. Step 3: Cross multiply
    661.69x = 912.08 × 521.58
  4. Step 4: Simplify right side
    661.69x = 475,722.69
  5. Step 5: Solve for x
    x = 475,722.69/661.69
  6. Step 6: Final answer
    x = 718.95

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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.