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Finding the Fourth Proportional to 135.79, 187.30 and 100.81

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Solution

The fourth proportional to 135.79, 187.30 and 100.81 is: 139.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    135.79 : 187.30 = 100.81 : x
  2. Step 2: Convert to fraction form
    135.79/187.30 = 100.81/x
  3. Step 3: Cross multiply
    135.79x = 187.30 × 100.81
  4. Step 4: Simplify right side
    135.79x = 18,881.71
  5. Step 5: Solve for x
    x = 18,881.71/135.79
  6. Step 6: Final answer
    x = 139.05

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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.