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Finding the Fourth Proportional to 687.51, 948.38 and 407.57

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Solution

The fourth proportional to 687.51, 948.38 and 407.57 is: 562.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.51 : 948.38 = 407.57 : x
  2. Step 2: Convert to fraction form
    687.51/948.38 = 407.57/x
  3. Step 3: Cross multiply
    687.51x = 948.38 × 407.57
  4. Step 4: Simplify right side
    687.51x = 386,524.46
  5. Step 5: Solve for x
    x = 386,524.46/687.51
  6. Step 6: Final answer
    x = 562.21

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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.