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Finding the Fourth Proportional to 1,258.57, 1,886.37 and 642.57

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Solution

The fourth proportional to 1,258.57, 1,886.37 and 642.57 is: 963.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,258.57 : 1,886.37 = 642.57 : x
  2. Step 2: Convert to fraction form
    1,258.57/1,886.37 = 642.57/x
  3. Step 3: Cross multiply
    1,258.57x = 1,886.37 × 642.57
  4. Step 4: Simplify right side
    1,258.57x = 1,212,124.77
  5. Step 5: Solve for x
    x = 1,212,124.77/1,258.57
  6. Step 6: Final answer
    x = 963.10

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.