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Finding the Fourth Proportional to 109.23, 150.63 and 90.78

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Solution

The fourth proportional to 109.23, 150.63 and 90.78 is: 125.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    109.23 : 150.63 = 90.78 : x
  2. Step 2: Convert to fraction form
    109.23/150.63 = 90.78/x
  3. Step 3: Cross multiply
    109.23x = 150.63 × 90.78
  4. Step 4: Simplify right side
    109.23x = 13,674.19
  5. Step 5: Solve for x
    x = 13,674.19/109.23
  6. Step 6: Final answer
    x = 125.19

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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.