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Finding the Fourth Proportional to 690.51, 940.14 and 688.35

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Solution

The fourth proportional to 690.51, 940.14 and 688.35 is: 937.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.51 : 940.14 = 688.35 : x
  2. Step 2: Convert to fraction form
    690.51/940.14 = 688.35/x
  3. Step 3: Cross multiply
    690.51x = 940.14 × 688.35
  4. Step 4: Simplify right side
    690.51x = 647,145.37
  5. Step 5: Solve for x
    x = 647,145.37/690.51
  6. Step 6: Final answer
    x = 937.20

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.