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Finding the Fourth Proportional to 620.88, 931.32 and 255.78

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Solution

The fourth proportional to 620.88, 931.32 and 255.78 is: 383.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.88 : 931.32 = 255.78 : x
  2. Step 2: Convert to fraction form
    620.88/931.32 = 255.78/x
  3. Step 3: Cross multiply
    620.88x = 931.32 × 255.78
  4. Step 4: Simplify right side
    620.88x = 238,213.03
  5. Step 5: Solve for x
    x = 238,213.03/620.88
  6. Step 6: Final answer
    x = 383.67

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Similar ratio
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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.