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Finding the Fourth Proportional to 645.19, 890.37 and 365.45

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Solution

The fourth proportional to 645.19, 890.37 and 365.45 is: 504.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.19 : 890.37 = 365.45 : x
  2. Step 2: Convert to fraction form
    645.19/890.37 = 365.45/x
  3. Step 3: Cross multiply
    645.19x = 890.37 × 365.45
  4. Step 4: Simplify right side
    645.19x = 325,381.26
  5. Step 5: Solve for x
    x = 325,381.26/645.19
  6. Step 6: Final answer
    x = 504.32

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.