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Finding the Fourth Proportional to 154.80, 212.40 and 145.80

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Solution

The fourth proportional to 154.80, 212.40 and 145.80 is: 200.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.80 : 212.40 = 145.80 : x
  2. Step 2: Convert to fraction form
    154.80/212.40 = 145.80/x
  3. Step 3: Cross multiply
    154.80x = 212.40 × 145.80
  4. Step 4: Simplify right side
    154.80x = 30,967.92
  5. Step 5: Solve for x
    x = 30,967.92/154.80
  6. Step 6: Final answer
    x = 200.05

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.