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Finding the Fourth Proportional to 661.45, 910.71 and 561.66

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Solution

The fourth proportional to 661.45, 910.71 and 561.66 is: 773.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.45 : 910.71 = 561.66 : x
  2. Step 2: Convert to fraction form
    661.45/910.71 = 561.66/x
  3. Step 3: Cross multiply
    661.45x = 910.71 × 561.66
  4. Step 4: Simplify right side
    661.45x = 511,513.85
  5. Step 5: Solve for x
    x = 511,513.85/661.45
  6. Step 6: Final answer
    x = 773.33

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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.