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Finding the Fourth Proportional to 830.80, 1,248.90 and 782.20

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Solution

The fourth proportional to 830.80, 1,248.90 and 782.20 is: 1,175.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.80 : 1,248.90 = 782.20 : x
  2. Step 2: Convert to fraction form
    830.80/1,248.90 = 782.20/x
  3. Step 3: Cross multiply
    830.80x = 1,248.90 × 782.20
  4. Step 4: Simplify right side
    830.80x = 976,889.58
  5. Step 5: Solve for x
    x = 976,889.58/830.80
  6. Step 6: Final answer
    x = 1,175.84

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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.