Finding the Fourth Proportional to 138.21, 206.79 and 118.68
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Solution
The fourth proportional to 138.21, 206.79 and 118.68 is: 177.57
Step by Step Solution
- Step 1: Write the proportion equation
138.21 : 206.79 = 118.68 : x - Step 2: Convert to fraction form
138.21/206.79 = 118.68/x - Step 3: Cross multiply
138.21x = 206.79 × 118.68 - Step 4: Simplify right side
138.21x = 24,541.84 - Step 5: Solve for x
x = 24,541.84/138.21 - Step 6: Final answer
x = 177.57
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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.