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Finding the Fourth Proportional to 618.42, 853.70 and 419.50

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Solution

The fourth proportional to 618.42, 853.70 and 419.50 is: 579.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.42 : 853.70 = 419.50 : x
  2. Step 2: Convert to fraction form
    618.42/853.70 = 419.50/x
  3. Step 3: Cross multiply
    618.42x = 853.70 × 419.50
  4. Step 4: Simplify right side
    618.42x = 358,127.15
  5. Step 5: Solve for x
    x = 358,127.15/618.42
  6. Step 6: Final answer
    x = 579.10

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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.