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Finding the Third Proportional to 278 and 490

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Solution

The third proportional to 278 and 490 is: 863.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    278 : 490 = 490 : x
  2. Step 2: Convert to fraction form
    278/490 = 490/x
  3. Step 3: Cross multiply
    278x = 490 × 490
  4. Step 4: Simplify right side
    278x = 240,100
  5. Step 5: Solve for x
    x = 240,100/278
  6. Step 6: Final answer
    x = 863.67

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Why These Related Problems?

These problems maintain the same ratio (1.76) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.