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Finding the Fourth Proportional to 390.06, 538.29 and 258.84

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Solution

The fourth proportional to 390.06, 538.29 and 258.84 is: 357.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.06 : 538.29 = 258.84 : x
  2. Step 2: Convert to fraction form
    390.06/538.29 = 258.84/x
  3. Step 3: Cross multiply
    390.06x = 538.29 × 258.84
  4. Step 4: Simplify right side
    390.06x = 139,330.98
  5. Step 5: Solve for x
    x = 139,330.98/390.06
  6. Step 6: Final answer
    x = 357.20

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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.