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Finding the Fourth Proportional to 218.40, 325.62 and 212.70

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Solution

The fourth proportional to 218.40, 325.62 and 212.70 is: 317.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.40 : 325.62 = 212.70 : x
  2. Step 2: Convert to fraction form
    218.40/325.62 = 212.70/x
  3. Step 3: Cross multiply
    218.40x = 325.62 × 212.70
  4. Step 4: Simplify right side
    218.40x = 69,259.37
  5. Step 5: Solve for x
    x = 69,259.37/218.40
  6. Step 6: Final answer
    x = 317.12

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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.