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Finding the Fourth Proportional to 280.09, 386.51 and 154.05

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Solution

The fourth proportional to 280.09, 386.51 and 154.05 is: 212.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.09 : 386.51 = 154.05 : x
  2. Step 2: Convert to fraction form
    280.09/386.51 = 154.05/x
  3. Step 3: Cross multiply
    280.09x = 386.51 × 154.05
  4. Step 4: Simplify right side
    280.09x = 59,541.87
  5. Step 5: Solve for x
    x = 59,541.87/280.09
  6. Step 6: Final answer
    x = 212.58

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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.