Finding the Fourth Proportional to 138.74, 207.90 and 77.99
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Solution
The fourth proportional to 138.74, 207.90 and 77.99 is: 116.86
Step by Step Solution
- Step 1: Write the proportion equation
138.74 : 207.90 = 77.99 : x - Step 2: Convert to fraction form
138.74/207.90 = 77.99/x - Step 3: Cross multiply
138.74x = 207.90 × 77.99 - Step 4: Simplify right side
138.74x = 16,213.08 - Step 5: Solve for x
x = 16,213.08/138.74 - Step 6: Final answer
x = 116.86
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.