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Finding the Fourth Proportional to 620.06, 855.29 and 380.70

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Solution

The fourth proportional to 620.06, 855.29 and 380.70 is: 525.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.06 : 855.29 = 380.70 : x
  2. Step 2: Convert to fraction form
    620.06/855.29 = 380.70/x
  3. Step 3: Cross multiply
    620.06x = 855.29 × 380.70
  4. Step 4: Simplify right side
    620.06x = 325,609.85
  5. Step 5: Solve for x
    x = 325,609.85/620.06
  6. Step 6: Final answer
    x = 525.13

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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.