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Finding the Fourth Proportional to 669.40, 998.81 and 561.40

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Solution

The fourth proportional to 669.40, 998.81 and 561.40 is: 837.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.40 : 998.81 = 561.40 : x
  2. Step 2: Convert to fraction form
    669.40/998.81 = 561.40/x
  3. Step 3: Cross multiply
    669.40x = 998.81 × 561.40
  4. Step 4: Simplify right side
    669.40x = 560,731.93
  5. Step 5: Solve for x
    x = 560,731.93/669.40
  6. Step 6: Final answer
    x = 837.66

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.