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Finding the Fourth Proportional to 672.99, 928.78 and 378.31

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Solution

The fourth proportional to 672.99, 928.78 and 378.31 is: 522.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    672.99 : 928.78 = 378.31 : x
  2. Step 2: Convert to fraction form
    672.99/928.78 = 378.31/x
  3. Step 3: Cross multiply
    672.99x = 928.78 × 378.31
  4. Step 4: Simplify right side
    672.99x = 351,364.87
  5. Step 5: Solve for x
    x = 351,364.87/672.99
  6. Step 6: Final answer
    x = 522.10

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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.