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Finding the Fourth Proportional to 821.32, 1,228.62 and 684.56

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Solution

The fourth proportional to 821.32, 1,228.62 and 684.56 is: 1,024.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.32 : 1,228.62 = 684.56 : x
  2. Step 2: Convert to fraction form
    821.32/1,228.62 = 684.56/x
  3. Step 3: Cross multiply
    821.32x = 1,228.62 × 684.56
  4. Step 4: Simplify right side
    821.32x = 841,064.11
  5. Step 5: Solve for x
    x = 841,064.11/821.32
  6. Step 6: Final answer
    x = 1,024.04

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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.