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Finding the Fourth Proportional to 643.82, 965.72 and 259.34

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Solution

The fourth proportional to 643.82, 965.72 and 259.34 is: 389.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.82 : 965.72 = 259.34 : x
  2. Step 2: Convert to fraction form
    643.82/965.72 = 259.34/x
  3. Step 3: Cross multiply
    643.82x = 965.72 × 259.34
  4. Step 4: Simplify right side
    643.82x = 250,445.64
  5. Step 5: Solve for x
    x = 250,445.64/643.82
  6. Step 6: Final answer
    x = 389.00

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Double scale
Find fourth proportional to 644.82, 967.22 and 260.34
Similar ratio
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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.