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Finding the Fourth Proportional to 955.86, 1,319.49 and 645.78

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Solution

The fourth proportional to 955.86, 1,319.49 and 645.78 is: 891.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    955.86 : 1,319.49 = 645.78 : x
  2. Step 2: Convert to fraction form
    955.86/1,319.49 = 645.78/x
  3. Step 3: Cross multiply
    955.86x = 1,319.49 × 645.78
  4. Step 4: Simplify right side
    955.86x = 852,100.25
  5. Step 5: Solve for x
    x = 852,100.25/955.86
  6. Step 6: Final answer
    x = 891.45

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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.