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Finding the Fourth Proportional to 390.69, 535.66 and 383.81

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Solution

The fourth proportional to 390.69, 535.66 and 383.81 is: 526.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.69 : 535.66 = 383.81 : x
  2. Step 2: Convert to fraction form
    390.69/535.66 = 383.81/x
  3. Step 3: Cross multiply
    390.69x = 535.66 × 383.81
  4. Step 4: Simplify right side
    390.69x = 205,590.33
  5. Step 5: Solve for x
    x = 205,590.33/390.69
  6. Step 6: Final answer
    x = 526.22

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.