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Finding the Fourth Proportional to 830.58, 1,243 and 518.10

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Solution

The fourth proportional to 830.58, 1,243 and 518.10 is: 775.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.58 : 1,243 = 518.10 : x
  2. Step 2: Convert to fraction form
    830.58/1,243 = 518.10/x
  3. Step 3: Cross multiply
    830.58x = 1,243 × 518.10
  4. Step 4: Simplify right side
    830.58x = 643,998.30
  5. Step 5: Solve for x
    x = 643,998.30/830.58
  6. Step 6: Final answer
    x = 775.36

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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.