Finding the Fourth Proportional to 398.84, 550.39 and 221.81
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Solution
The fourth proportional to 398.84, 550.39 and 221.81 is: 306.09
Step by Step Solution
- Step 1: Write the proportion equation
398.84 : 550.39 = 221.81 : x - Step 2: Convert to fraction form
398.84/550.39 = 221.81/x - Step 3: Cross multiply
398.84x = 550.39 × 221.81 - Step 4: Simplify right side
398.84x = 122,079.25 - Step 5: Solve for x
x = 122,079.25/398.84 - Step 6: Final answer
x = 306.09
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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.