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Finding the Fourth Proportional to 155.39, 214.43 and 89.90

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Solution

The fourth proportional to 155.39, 214.43 and 89.90 is: 124.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.39 : 214.43 = 89.90 : x
  2. Step 2: Convert to fraction form
    155.39/214.43 = 89.90/x
  3. Step 3: Cross multiply
    155.39x = 214.43 × 89.90
  4. Step 4: Simplify right side
    155.39x = 19,275.74
  5. Step 5: Solve for x
    x = 19,275.74/155.39
  6. Step 6: Final answer
    x = 124.05

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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.