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Finding the Fourth Proportional to 661.23, 912.33 and 399.06

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Solution

The fourth proportional to 661.23, 912.33 and 399.06 is: 550.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.23 : 912.33 = 399.06 : x
  2. Step 2: Convert to fraction form
    661.23/912.33 = 399.06/x
  3. Step 3: Cross multiply
    661.23x = 912.33 × 399.06
  4. Step 4: Simplify right side
    661.23x = 364,074.41
  5. Step 5: Solve for x
    x = 364,074.41/661.23
  6. Step 6: Final answer
    x = 550.60

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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.