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Finding the Fourth Proportional to 608.69, 840.30 and 387.94

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Solution

The fourth proportional to 608.69, 840.30 and 387.94 is: 535.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.69 : 840.30 = 387.94 : x
  2. Step 2: Convert to fraction form
    608.69/840.30 = 387.94/x
  3. Step 3: Cross multiply
    608.69x = 840.30 × 387.94
  4. Step 4: Simplify right side
    608.69x = 325,985.98
  5. Step 5: Solve for x
    x = 325,985.98/608.69
  6. Step 6: Final answer
    x = 535.55

Related Problems

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Double scale
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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.