Finding the Fourth Proportional to 208.40, 312.42 and 98.72
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Solution
The fourth proportional to 208.40, 312.42 and 98.72 is: 147.99
Step by Step Solution
- Step 1: Write the proportion equation
208.40 : 312.42 = 98.72 : x - Step 2: Convert to fraction form
208.40/312.42 = 98.72/x - Step 3: Cross multiply
208.40x = 312.42 × 98.72 - Step 4: Simplify right side
208.40x = 30,842.10 - Step 5: Solve for x
x = 30,842.10/208.40 - Step 6: Final answer
x = 147.99
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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.