Finding the Fourth Proportional to 138.60, 207.84 and 70.08
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Solution
The fourth proportional to 138.60, 207.84 and 70.08 is: 105.09
Step by Step Solution
- Step 1: Write the proportion equation
138.60 : 207.84 = 70.08 : x - Step 2: Convert to fraction form
138.60/207.84 = 70.08/x - Step 3: Cross multiply
138.60x = 207.84 × 70.08 - Step 4: Simplify right side
138.60x = 14,565.43 - Step 5: Solve for x
x = 14,565.43/138.60 - Step 6: Final answer
x = 105.09
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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.