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Finding the Fourth Proportional to 287.70, 397.02 and 156.70

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Solution

The fourth proportional to 287.70, 397.02 and 156.70 is: 216.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.70 : 397.02 = 156.70 : x
  2. Step 2: Convert to fraction form
    287.70/397.02 = 156.70/x
  3. Step 3: Cross multiply
    287.70x = 397.02 × 156.70
  4. Step 4: Simplify right side
    287.70x = 62,214.27
  5. Step 5: Solve for x
    x = 62,214.27/287.70
  6. Step 6: Final answer
    x = 216.25

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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.