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Finding the Fourth Proportional to 784.32, 1,081.08 and 644.19

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Solution

The fourth proportional to 784.32, 1,081.08 and 644.19 is: 887.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.32 : 1,081.08 = 644.19 : x
  2. Step 2: Convert to fraction form
    784.32/1,081.08 = 644.19/x
  3. Step 3: Cross multiply
    784.32x = 1,081.08 × 644.19
  4. Step 4: Simplify right side
    784.32x = 696,420.93
  5. Step 5: Solve for x
    x = 696,420.93/784.32
  6. Step 6: Final answer
    x = 887.93

Related Problems

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Half scale
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Double scale
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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.