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Finding the Fourth Proportional to 689.30, 953.10 and 678.17

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Solution

The fourth proportional to 689.30, 953.10 and 678.17 is: 937.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.30 : 953.10 = 678.17 : x
  2. Step 2: Convert to fraction form
    689.30/953.10 = 678.17/x
  3. Step 3: Cross multiply
    689.30x = 953.10 × 678.17
  4. Step 4: Simplify right side
    689.30x = 646,363.83
  5. Step 5: Solve for x
    x = 646,363.83/689.30
  6. Step 6: Final answer
    x = 937.72

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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.