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Finding the Fourth Proportional to 712.45, 983.08 and 397.72

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Solution

The fourth proportional to 712.45, 983.08 and 397.72 is: 548.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.45 : 983.08 = 397.72 : x
  2. Step 2: Convert to fraction form
    712.45/983.08 = 397.72/x
  3. Step 3: Cross multiply
    712.45x = 983.08 × 397.72
  4. Step 4: Simplify right side
    712.45x = 390,990.58
  5. Step 5: Solve for x
    x = 390,990.58/712.45
  6. Step 6: Final answer
    x = 548.80

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1.5x scale

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.