Finding the Fourth Proportional to 90.20, 135.18 and 68.72
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Solution
The fourth proportional to 90.20, 135.18 and 68.72 is: 102.99
Step by Step Solution
- Step 1: Write the proportion equation
90.20 : 135.18 = 68.72 : x - Step 2: Convert to fraction form
90.20/135.18 = 68.72/x - Step 3: Cross multiply
90.20x = 135.18 × 68.72 - Step 4: Simplify right side
90.20x = 9,289.57 - Step 5: Solve for x
x = 9,289.57/90.20 - Step 6: Final answer
x = 102.99
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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.