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Finding the Fourth Proportional to 703.80, 969.30 and 639

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Solution

The fourth proportional to 703.80, 969.30 and 639 is: 880.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    703.80 : 969.30 = 639 : x
  2. Step 2: Convert to fraction form
    703.80/969.30 = 639/x
  3. Step 3: Cross multiply
    703.80x = 969.30 × 639
  4. Step 4: Simplify right side
    703.80x = 619,382.70
  5. Step 5: Solve for x
    x = 619,382.70/703.80
  6. Step 6: Final answer
    x = 880.05

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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.