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Finding the Fourth Proportional to 981.55, 1,354.61 and 649.40

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Solution

The fourth proportional to 981.55, 1,354.61 and 649.40 is: 896.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    981.55 : 1,354.61 = 649.40 : x
  2. Step 2: Convert to fraction form
    981.55/1,354.61 = 649.40/x
  3. Step 3: Cross multiply
    981.55x = 1,354.61 × 649.40
  4. Step 4: Simplify right side
    981.55x = 879,683.73
  5. Step 5: Solve for x
    x = 879,683.73/981.55
  6. Step 6: Final answer
    x = 896.22

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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.