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Finding the Fourth Proportional to 912.70, 1,258.23 and 649.90

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Solution

The fourth proportional to 912.70, 1,258.23 and 649.90 is: 895.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    912.70 : 1,258.23 = 649.90 : x
  2. Step 2: Convert to fraction form
    912.70/1,258.23 = 649.90/x
  3. Step 3: Cross multiply
    912.70x = 1,258.23 × 649.90
  4. Step 4: Simplify right side
    912.70x = 817,723.68
  5. Step 5: Solve for x
    x = 817,723.68/912.70
  6. Step 6: Final answer
    x = 895.94

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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.