Finding the Fourth Proportional to 98.79, 135.99 and 84.21
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Solution
The fourth proportional to 98.79, 135.99 and 84.21 is: 115.92
Step by Step Solution
- Step 1: Write the proportion equation
98.79 : 135.99 = 84.21 : x - Step 2: Convert to fraction form
98.79/135.99 = 84.21/x - Step 3: Cross multiply
98.79x = 135.99 × 84.21 - Step 4: Simplify right side
98.79x = 11,451.72 - Step 5: Solve for x
x = 11,451.72/98.79 - Step 6: Final answer
x = 115.92
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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.