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Finding the Fourth Proportional to 653.70, 980.78 and 288.45

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Solution

The fourth proportional to 653.70, 980.78 and 288.45 is: 432.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.70 : 980.78 = 288.45 : x
  2. Step 2: Convert to fraction form
    653.70/980.78 = 288.45/x
  3. Step 3: Cross multiply
    653.70x = 980.78 × 288.45
  4. Step 4: Simplify right side
    653.70x = 282,905.99
  5. Step 5: Solve for x
    x = 282,905.99/653.70
  6. Step 6: Final answer
    x = 432.78

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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.