Finding the Fourth Proportional to 100.79, 138.98 and 87.02
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Solution
The fourth proportional to 100.79, 138.98 and 87.02 is: 119.99
Step by Step Solution
- Step 1: Write the proportion equation
100.79 : 138.98 = 87.02 : x - Step 2: Convert to fraction form
100.79/138.98 = 87.02/x - Step 3: Cross multiply
100.79x = 138.98 × 87.02 - Step 4: Simplify right side
100.79x = 12,094.04 - Step 5: Solve for x
x = 12,094.04/100.79 - Step 6: Final answer
x = 119.99
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.