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Finding the Fourth Proportional to 287.59, 429.70 and 213.15

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Solution

The fourth proportional to 287.59, 429.70 and 213.15 is: 318.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.59 : 429.70 = 213.15 : x
  2. Step 2: Convert to fraction form
    287.59/429.70 = 213.15/x
  3. Step 3: Cross multiply
    287.59x = 429.70 × 213.15
  4. Step 4: Simplify right side
    287.59x = 91,587.34
  5. Step 5: Solve for x
    x = 91,587.34/287.59
  6. Step 6: Final answer
    x = 318.47

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.