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Finding the Fourth Proportional to 390.04, 538.25 and 212.99

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Solution

The fourth proportional to 390.04, 538.25 and 212.99 is: 293.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.04 : 538.25 = 212.99 : x
  2. Step 2: Convert to fraction form
    390.04/538.25 = 212.99/x
  3. Step 3: Cross multiply
    390.04x = 538.25 × 212.99
  4. Step 4: Simplify right side
    390.04x = 114,640.80
  5. Step 5: Solve for x
    x = 114,640.80/390.04
  6. Step 6: Final answer
    x = 293.92

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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.