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Finding the Fourth Proportional to 390.03, 538.05 and 285.06

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Solution

The fourth proportional to 390.03, 538.05 and 285.06 is: 393.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.03 : 538.05 = 285.06 : x
  2. Step 2: Convert to fraction form
    390.03/538.05 = 285.06/x
  3. Step 3: Cross multiply
    390.03x = 538.05 × 285.06
  4. Step 4: Simplify right side
    390.03x = 153,376.53
  5. Step 5: Solve for x
    x = 153,376.53/390.03
  6. Step 6: Final answer
    x = 393.24

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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.