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Finding the Fourth Proportional to 612.30, 919.32 and 380.45

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Solution

The fourth proportional to 612.30, 919.32 and 380.45 is: 571.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.30 : 919.32 = 380.45 : x
  2. Step 2: Convert to fraction form
    612.30/919.32 = 380.45/x
  3. Step 3: Cross multiply
    612.30x = 919.32 × 380.45
  4. Step 4: Simplify right side
    612.30x = 349,750.70
  5. Step 5: Solve for x
    x = 349,750.70/612.30
  6. Step 6: Final answer
    x = 571.21

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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.