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Finding the Fourth Proportional to 711.21, 981.40 and 524.80

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Solution

The fourth proportional to 711.21, 981.40 and 524.80 is: 724.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.21 : 981.40 = 524.80 : x
  2. Step 2: Convert to fraction form
    711.21/981.40 = 524.80/x
  3. Step 3: Cross multiply
    711.21x = 981.40 × 524.80
  4. Step 4: Simplify right side
    711.21x = 515,038.72
  5. Step 5: Solve for x
    x = 515,038.72/711.21
  6. Step 6: Final answer
    x = 724.17

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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.