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Finding the Fourth Proportional to 1,293.40, 1,940.10 and 427.78

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Solution

The fourth proportional to 1,293.40, 1,940.10 and 427.78 is: 641.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,293.40 : 1,940.10 = 427.78 : x
  2. Step 2: Convert to fraction form
    1,293.40/1,940.10 = 427.78/x
  3. Step 3: Cross multiply
    1,293.40x = 1,940.10 × 427.78
  4. Step 4: Simplify right side
    1,293.40x = 829,935.98
  5. Step 5: Solve for x
    x = 829,935.98/1,293.40
  6. Step 6: Final answer
    x = 641.67

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.