Finding the Fourth Proportional to 390.19, 538 and 319.99
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Solution
The fourth proportional to 390.19, 538 and 319.99 is: 441.21
Step by Step Solution
- Step 1: Write the proportion equation
390.19 : 538 = 319.99 : x - Step 2: Convert to fraction form
390.19/538 = 319.99/x - Step 3: Cross multiply
390.19x = 538 × 319.99 - Step 4: Simplify right side
390.19x = 172,154.62 - Step 5: Solve for x
x = 172,154.62/390.19 - Step 6: Final answer
x = 441.21
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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.