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Finding the Fourth Proportional to 711.39, 981.78 and 400.89

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Solution

The fourth proportional to 711.39, 981.78 and 400.89 is: 553.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.39 : 981.78 = 400.89 : x
  2. Step 2: Convert to fraction form
    711.39/981.78 = 400.89/x
  3. Step 3: Cross multiply
    711.39x = 981.78 × 400.89
  4. Step 4: Simplify right side
    711.39x = 393,585.78
  5. Step 5: Solve for x
    x = 393,585.78/711.39
  6. Step 6: Final answer
    x = 553.26

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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.