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Finding the Fourth Proportional to 830.60, 1,246.80 and 648.80

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Solution

The fourth proportional to 830.60, 1,246.80 and 648.80 is: 973.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.60 : 1,246.80 = 648.80 : x
  2. Step 2: Convert to fraction form
    830.60/1,246.80 = 648.80/x
  3. Step 3: Cross multiply
    830.60x = 1,246.80 × 648.80
  4. Step 4: Simplify right side
    830.60x = 808,923.84
  5. Step 5: Solve for x
    x = 808,923.84/830.60
  6. Step 6: Final answer
    x = 973.90

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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.