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Finding the Fourth Proportional to 928.08, 1,280.64 and 648.96

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Solution

The fourth proportional to 928.08, 1,280.64 and 648.96 is: 895.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    928.08 : 1,280.64 = 648.96 : x
  2. Step 2: Convert to fraction form
    928.08/1,280.64 = 648.96/x
  3. Step 3: Cross multiply
    928.08x = 1,280.64 × 648.96
  4. Step 4: Simplify right side
    928.08x = 831,084.13
  5. Step 5: Solve for x
    x = 831,084.13/928.08
  6. Step 6: Final answer
    x = 895.49

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.