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Finding the Fourth Proportional to 710.40, 981.36 and 688.80

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Solution

The fourth proportional to 710.40, 981.36 and 688.80 is: 951.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    710.40 : 981.36 = 688.80 : x
  2. Step 2: Convert to fraction form
    710.40/981.36 = 688.80/x
  3. Step 3: Cross multiply
    710.40x = 981.36 × 688.80
  4. Step 4: Simplify right side
    710.40x = 675,960.77
  5. Step 5: Solve for x
    x = 675,960.77/710.40
  6. Step 6: Final answer
    x = 951.52

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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.