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Finding the Fourth Proportional to 665.90, 918.90 and 371.19

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Solution

The fourth proportional to 665.90, 918.90 and 371.19 is: 512.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.90 : 918.90 = 371.19 : x
  2. Step 2: Convert to fraction form
    665.90/918.90 = 371.19/x
  3. Step 3: Cross multiply
    665.90x = 918.90 × 371.19
  4. Step 4: Simplify right side
    665.90x = 341,084.77
  5. Step 5: Solve for x
    x = 341,084.77/665.90
  6. Step 6: Final answer
    x = 512.21

Related Problems

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Half scale
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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 (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.