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Finding the Fourth Proportional to 869.05, 1,308.76 and 724.20

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Solution

The fourth proportional to 869.05, 1,308.76 and 724.20 is: 1,090.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.05 : 1,308.76 = 724.20 : x
  2. Step 2: Convert to fraction form
    869.05/1,308.76 = 724.20/x
  3. Step 3: Cross multiply
    869.05x = 1,308.76 × 724.20
  4. Step 4: Simplify right side
    869.05x = 947,803.99
  5. Step 5: Solve for x
    x = 947,803.99/869.05
  6. Step 6: Final answer
    x = 1,090.62

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.