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Finding the Fourth Proportional to 689.70, 952.25 and 645.63

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Solution

The fourth proportional to 689.70, 952.25 and 645.63 is: 891.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.70 : 952.25 = 645.63 : x
  2. Step 2: Convert to fraction form
    689.70/952.25 = 645.63/x
  3. Step 3: Cross multiply
    689.70x = 952.25 × 645.63
  4. Step 4: Simplify right side
    689.70x = 614,801.17
  5. Step 5: Solve for x
    x = 614,801.17/689.70
  6. Step 6: Final answer
    x = 891.40

Related Problems

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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.