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Finding the Fourth Proportional to 620.90, 930.81 and 312.49

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Solution

The fourth proportional to 620.90, 930.81 and 312.49 is: 468.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.90 : 930.81 = 312.49 : x
  2. Step 2: Convert to fraction form
    620.90/930.81 = 312.49/x
  3. Step 3: Cross multiply
    620.90x = 930.81 × 312.49
  4. Step 4: Simplify right side
    620.90x = 290,867.25
  5. Step 5: Solve for x
    x = 290,867.25/620.90
  6. Step 6: Final answer
    x = 468.46

Related Problems

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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.