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Finding the Fourth Proportional to 390.83, 538.83 and 302.16

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Solution

The fourth proportional to 390.83, 538.83 and 302.16 is: 416.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.83 : 538.83 = 302.16 : x
  2. Step 2: Convert to fraction form
    390.83/538.83 = 302.16/x
  3. Step 3: Cross multiply
    390.83x = 538.83 × 302.16
  4. Step 4: Simplify right side
    390.83x = 162,812.87
  5. Step 5: Solve for x
    x = 162,812.87/390.83
  6. Step 6: Final answer
    x = 416.58

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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.