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Finding the Fourth Proportional to 155.40, 214.56 and 100.28

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Solution

The fourth proportional to 155.40, 214.56 and 100.28 is: 138.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.40 : 214.56 = 100.28 : x
  2. Step 2: Convert to fraction form
    155.40/214.56 = 100.28/x
  3. Step 3: Cross multiply
    155.40x = 214.56 × 100.28
  4. Step 4: Simplify right side
    155.40x = 21,516.08
  5. Step 5: Solve for x
    x = 21,516.08/155.40
  6. Step 6: Final answer
    x = 138.46

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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.