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Finding the Fourth Proportional to 618.80, 853.90 and 370.15

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Solution

The fourth proportional to 618.80, 853.90 and 370.15 is: 510.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.80 : 853.90 = 370.15 : x
  2. Step 2: Convert to fraction form
    618.80/853.90 = 370.15/x
  3. Step 3: Cross multiply
    618.80x = 853.90 × 370.15
  4. Step 4: Simplify right side
    618.80x = 316,068.02
  5. Step 5: Solve for x
    x = 316,068.02/618.80
  6. Step 6: Final answer
    x = 510.78

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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.