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Finding the Fourth Proportional to 827.80, 1,242.30 and 646.75

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Solution

The fourth proportional to 827.80, 1,242.30 and 646.75 is: 970.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    827.80 : 1,242.30 = 646.75 : x
  2. Step 2: Convert to fraction form
    827.80/1,242.30 = 646.75/x
  3. Step 3: Cross multiply
    827.80x = 1,242.30 × 646.75
  4. Step 4: Simplify right side
    827.80x = 803,457.53
  5. Step 5: Solve for x
    x = 803,457.53/827.80
  6. Step 6: Final answer
    x = 970.59

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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.