Finding the Fourth Proportional to 378.99, 523.05 and 221.70
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Solution
The fourth proportional to 378.99, 523.05 and 221.70 is: 305.97
Step by Step Solution
- Step 1: Write the proportion equation
378.99 : 523.05 = 221.70 : x - Step 2: Convert to fraction form
378.99/523.05 = 221.70/x - Step 3: Cross multiply
378.99x = 523.05 × 221.70 - Step 4: Simplify right side
378.99x = 115,961.32 - Step 5: Solve for x
x = 115,961.32/378.99 - Step 6: Final answer
x = 305.97
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.