Finding the Fourth Proportional to 100.64, 138.89 and 56.99
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Solution
The fourth proportional to 100.64, 138.89 and 56.99 is: 78.65
Step by Step Solution
- Step 1: Write the proportion equation
100.64 : 138.89 = 56.99 : x - Step 2: Convert to fraction form
100.64/138.89 = 56.99/x - Step 3: Cross multiply
100.64x = 138.89 × 56.99 - Step 4: Simplify right side
100.64x = 7,915.83 - Step 5: Solve for x
x = 7,915.83/100.64 - Step 6: Final answer
x = 78.65
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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.