Finding the Fourth Proportional to 65.70, 90.72 and 56.99
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Solution
The fourth proportional to 65.70, 90.72 and 56.99 is: 78.70
Step by Step Solution
- Step 1: Write the proportion equation
65.70 : 90.72 = 56.99 : x - Step 2: Convert to fraction form
65.70/90.72 = 56.99/x - Step 3: Cross multiply
65.70x = 90.72 × 56.99 - Step 4: Simplify right side
65.70x = 5,170.36 - Step 5: Solve for x
x = 5,170.36/65.70 - Step 6: Final answer
x = 78.70
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.