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Finding the Fourth Proportional to 711.70, 981.89 and 401.20

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Solution

The fourth proportional to 711.70, 981.89 and 401.20 is: 553.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.70 : 981.89 = 401.20 : x
  2. Step 2: Convert to fraction form
    711.70/981.89 = 401.20/x
  3. Step 3: Cross multiply
    711.70x = 981.89 × 401.20
  4. Step 4: Simplify right side
    711.70x = 393,931.31
  5. Step 5: Solve for x
    x = 393,931.31/711.70
  6. Step 6: Final answer
    x = 553.51

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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.