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Finding the Fourth Proportional to 155.30, 214.29 and 89.79

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Solution

The fourth proportional to 155.30, 214.29 and 89.79 is: 123.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.30 : 214.29 = 89.79 : x
  2. Step 2: Convert to fraction form
    155.30/214.29 = 89.79/x
  3. Step 3: Cross multiply
    155.30x = 214.29 × 89.79
  4. Step 4: Simplify right side
    155.30x = 19,240.65
  5. Step 5: Solve for x
    x = 19,240.65/155.30
  6. Step 6: Final answer
    x = 123.90

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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.