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Finding the Fourth Proportional to 613.90, 921.45 and 306.10

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Solution

The fourth proportional to 613.90, 921.45 and 306.10 is: 459.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.90 : 921.45 = 306.10 : x
  2. Step 2: Convert to fraction form
    613.90/921.45 = 306.10/x
  3. Step 3: Cross multiply
    613.90x = 921.45 × 306.10
  4. Step 4: Simplify right side
    613.90x = 282,055.85
  5. Step 5: Solve for x
    x = 282,055.85/613.90
  6. Step 6: Final answer
    x = 459.45

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Double scale
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Similar ratio
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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.