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Finding the Fourth Proportional to 613.50, 919.14 and 420.18

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Solution

The fourth proportional to 613.50, 919.14 and 420.18 is: 629.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.50 : 919.14 = 420.18 : x
  2. Step 2: Convert to fraction form
    613.50/919.14 = 420.18/x
  3. Step 3: Cross multiply
    613.50x = 919.14 × 420.18
  4. Step 4: Simplify right side
    613.50x = 386,204.25
  5. Step 5: Solve for x
    x = 386,204.25/613.50
  6. Step 6: Final answer
    x = 629.51

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Double scale
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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.