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Finding the Fourth Proportional to 145.30, 200.38 and 120.70

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Solution

The fourth proportional to 145.30, 200.38 and 120.70 is: 166.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.30 : 200.38 = 120.70 : x
  2. Step 2: Convert to fraction form
    145.30/200.38 = 120.70/x
  3. Step 3: Cross multiply
    145.30x = 200.38 × 120.70
  4. Step 4: Simplify right side
    145.30x = 24,185.87
  5. Step 5: Solve for x
    x = 24,185.87/145.30
  6. Step 6: Final answer
    x = 166.45

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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.