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Finding the Fourth Proportional to 620.79, 931 and 210.12

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Solution

The fourth proportional to 620.79, 931 and 210.12 is: 315.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.79 : 931 = 210.12 : x
  2. Step 2: Convert to fraction form
    620.79/931 = 210.12/x
  3. Step 3: Cross multiply
    620.79x = 931 × 210.12
  4. Step 4: Simplify right side
    620.79x = 195,621.72
  5. Step 5: Solve for x
    x = 195,621.72/620.79
  6. Step 6: Final answer
    x = 315.12

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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.