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Finding the Fourth Proportional to 120.19, 180.30 and 47.05

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Solution

The fourth proportional to 120.19, 180.30 and 47.05 is: 70.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.19 : 180.30 = 47.05 : x
  2. Step 2: Convert to fraction form
    120.19/180.30 = 47.05/x
  3. Step 3: Cross multiply
    120.19x = 180.30 × 47.05
  4. Step 4: Simplify right side
    120.19x = 8,483.12
  5. Step 5: Solve for x
    x = 8,483.12/120.19
  6. Step 6: Final answer
    x = 70.58

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.