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Finding the Fourth Proportional to 689.10, 949.14 and 685.45

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Solution

The fourth proportional to 689.10, 949.14 and 685.45 is: 944.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.10 : 949.14 = 685.45 : x
  2. Step 2: Convert to fraction form
    689.10/949.14 = 685.45/x
  3. Step 3: Cross multiply
    689.10x = 949.14 × 685.45
  4. Step 4: Simplify right side
    689.10x = 650,588.01
  5. Step 5: Solve for x
    x = 650,588.01/689.10
  6. Step 6: Final answer
    x = 944.11

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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.