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Finding the Fourth Proportional to 612.90, 919.11 and 381.45

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Solution

The fourth proportional to 612.90, 919.11 and 381.45 is: 572.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.90 : 919.11 = 381.45 : x
  2. Step 2: Convert to fraction form
    612.90/919.11 = 381.45/x
  3. Step 3: Cross multiply
    612.90x = 919.11 × 381.45
  4. Step 4: Simplify right side
    612.90x = 350,594.51
  5. Step 5: Solve for x
    x = 350,594.51/612.90
  6. Step 6: Final answer
    x = 572.03

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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.