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Finding the Fourth Proportional to 690.72, 945.72 and 688.29

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Solution

The fourth proportional to 690.72, 945.72 and 688.29 is: 942.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.72 : 945.72 = 688.29 : x
  2. Step 2: Convert to fraction form
    690.72/945.72 = 688.29/x
  3. Step 3: Cross multiply
    690.72x = 945.72 × 688.29
  4. Step 4: Simplify right side
    690.72x = 650,929.62
  5. Step 5: Solve for x
    x = 650,929.62/690.72
  6. Step 6: Final answer
    x = 942.39

Related Problems

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Half scale
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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.