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Finding the Fourth Proportional to 712.04, 981.78 and 660.20

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Solution

The fourth proportional to 712.04, 981.78 and 660.20 is: 910.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.04 : 981.78 = 660.20 : x
  2. Step 2: Convert to fraction form
    712.04/981.78 = 660.20/x
  3. Step 3: Cross multiply
    712.04x = 981.78 × 660.20
  4. Step 4: Simplify right side
    712.04x = 648,171.16
  5. Step 5: Solve for x
    x = 648,171.16/712.04
  6. Step 6: Final answer
    x = 910.30

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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.