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Finding the Fourth Proportional to 640.69, 884.16 and 378.77

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Solution

The fourth proportional to 640.69, 884.16 and 378.77 is: 522.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.69 : 884.16 = 378.77 : x
  2. Step 2: Convert to fraction form
    640.69/884.16 = 378.77/x
  3. Step 3: Cross multiply
    640.69x = 884.16 × 378.77
  4. Step 4: Simplify right side
    640.69x = 334,888.86
  5. Step 5: Solve for x
    x = 334,888.86/640.69
  6. Step 6: Final answer
    x = 522.70

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.