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Finding the Fourth Proportional to 661.90, 913.39 and 413.31

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Solution

The fourth proportional to 661.90, 913.39 and 413.31 is: 570.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.90 : 913.39 = 413.31 : x
  2. Step 2: Convert to fraction form
    661.90/913.39 = 413.31/x
  3. Step 3: Cross multiply
    661.90x = 913.39 × 413.31
  4. Step 4: Simplify right side
    661.90x = 377,513.22
  5. Step 5: Solve for x
    x = 377,513.22/661.90
  6. Step 6: Final answer
    x = 570.35

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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.