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Finding the Fourth Proportional to 653.07, 979.62 and 287.78

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Solution

The fourth proportional to 653.07, 979.62 and 287.78 is: 431.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.07 : 979.62 = 287.78 : x
  2. Step 2: Convert to fraction form
    653.07/979.62 = 287.78/x
  3. Step 3: Cross multiply
    653.07x = 979.62 × 287.78
  4. Step 4: Simplify right side
    653.07x = 281,913.60
  5. Step 5: Solve for x
    x = 281,913.60/653.07
  6. Step 6: Final answer
    x = 431.67

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1.5x scale

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.