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Finding the Fourth Proportional to 1,012.50, 1,396.85 and 639.34

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Solution

The fourth proportional to 1,012.50, 1,396.85 and 639.34 is: 882.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,012.50 : 1,396.85 = 639.34 : x
  2. Step 2: Convert to fraction form
    1,012.50/1,396.85 = 639.34/x
  3. Step 3: Cross multiply
    1,012.50x = 1,396.85 × 639.34
  4. Step 4: Simplify right side
    1,012.50x = 893,062.08
  5. Step 5: Solve for x
    x = 893,062.08/1,012.50
  6. Step 6: Final answer
    x = 882.04

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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.