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Finding the Fourth Proportional to 661.67, 912.47 and 399.53

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Solution

The fourth proportional to 661.67, 912.47 and 399.53 is: 550.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.67 : 912.47 = 399.53 : x
  2. Step 2: Convert to fraction form
    661.67/912.47 = 399.53/x
  3. Step 3: Cross multiply
    661.67x = 912.47 × 399.53
  4. Step 4: Simplify right side
    661.67x = 364,559.42
  5. Step 5: Solve for x
    x = 364,559.42/661.67
  6. Step 6: Final answer
    x = 550.97

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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.