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Finding the Fourth Proportional to 788.49, 1,087.65 and 630.99

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Solution

The fourth proportional to 788.49, 1,087.65 and 630.99 is: 870.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    788.49 : 1,087.65 = 630.99 : x
  2. Step 2: Convert to fraction form
    788.49/1,087.65 = 630.99/x
  3. Step 3: Cross multiply
    788.49x = 1,087.65 × 630.99
  4. Step 4: Simplify right side
    788.49x = 686,296.27
  5. Step 5: Solve for x
    x = 686,296.27/788.49
  6. Step 6: Final answer
    x = 870.39

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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.