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Finding the Fourth Proportional to 1,245.88, 1,719.34 and 686.39

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Solution

The fourth proportional to 1,245.88, 1,719.34 and 686.39 is: 947.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,245.88 : 1,719.34 = 686.39 : x
  2. Step 2: Convert to fraction form
    1,245.88/1,719.34 = 686.39/x
  3. Step 3: Cross multiply
    1,245.88x = 1,719.34 × 686.39
  4. Step 4: Simplify right side
    1,245.88x = 1,180,127.47
  5. Step 5: Solve for x
    x = 1,180,127.47/1,245.88
  6. Step 6: Final answer
    x = 947.23

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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.