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Finding the Fourth Proportional to 618.12, 919.68 and 612.72

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Solution

The fourth proportional to 618.12, 919.68 and 612.72 is: 911.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.12 : 919.68 = 612.72 : x
  2. Step 2: Convert to fraction form
    618.12/919.68 = 612.72/x
  3. Step 3: Cross multiply
    618.12x = 919.68 × 612.72
  4. Step 4: Simplify right side
    618.12x = 563,506.33
  5. Step 5: Solve for x
    x = 563,506.33/618.12
  6. Step 6: Final answer
    x = 911.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.