Finding the Fourth Proportional to 42.65, 58.78 and 30.99
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Solution
The fourth proportional to 42.65, 58.78 and 30.99 is: 42.72
Step by Step Solution
- Step 1: Write the proportion equation
42.65 : 58.78 = 30.99 : x - Step 2: Convert to fraction form
42.65/58.78 = 30.99/x - Step 3: Cross multiply
42.65x = 58.78 × 30.99 - Step 4: Simplify right side
42.65x = 1,821.59 - Step 5: Solve for x
x = 1,821.59/42.65 - Step 6: Final answer
x = 42.72
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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.