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Finding the Fourth Proportional to 672.88, 928.64 and 378.20

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Solution

The fourth proportional to 672.88, 928.64 and 378.20 is: 521.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    672.88 : 928.64 = 378.20 : x
  2. Step 2: Convert to fraction form
    672.88/928.64 = 378.20/x
  3. Step 3: Cross multiply
    672.88x = 928.64 × 378.20
  4. Step 4: Simplify right side
    672.88x = 351,211.65
  5. Step 5: Solve for x
    x = 351,211.65/672.88
  6. Step 6: Final answer
    x = 521.95

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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.