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Finding the Fourth Proportional to 830.82, 1,246.99 and 420.25

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Solution

The fourth proportional to 830.82, 1,246.99 and 420.25 is: 630.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.82 : 1,246.99 = 420.25 : x
  2. Step 2: Convert to fraction form
    830.82/1,246.99 = 420.25/x
  3. Step 3: Cross multiply
    830.82x = 1,246.99 × 420.25
  4. Step 4: Simplify right side
    830.82x = 524,041.31
  5. Step 5: Solve for x
    x = 524,041.31/830.82
  6. Step 6: Final answer
    x = 630.75

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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.