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Finding the Fourth Proportional to 642.63, 964.25 and 612.86

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Solution

The fourth proportional to 642.63, 964.25 and 612.86 is: 919.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.63 : 964.25 = 612.86 : x
  2. Step 2: Convert to fraction form
    642.63/964.25 = 612.86/x
  3. Step 3: Cross multiply
    642.63x = 964.25 × 612.86
  4. Step 4: Simplify right side
    642.63x = 590,947.19
  5. Step 5: Solve for x
    x = 590,947.19/642.63
  6. Step 6: Final answer
    x = 919.58

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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.