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Finding the Fourth Proportional to 712.60, 981.42 and 661.57

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Solution

The fourth proportional to 712.60, 981.42 and 661.57 is: 911.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.60 : 981.42 = 661.57 : x
  2. Step 2: Convert to fraction form
    712.60/981.42 = 661.57/x
  3. Step 3: Cross multiply
    712.60x = 981.42 × 661.57
  4. Step 4: Simplify right side
    712.60x = 649,273.09
  5. Step 5: Solve for x
    x = 649,273.09/712.60
  6. Step 6: Final answer
    x = 911.14

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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.