Finding the Fourth Proportional to 390.99, 539.58 and 225.21
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Solution
The fourth proportional to 390.99, 539.58 and 225.21 is: 310.80
Step by Step Solution
- Step 1: Write the proportion equation
390.99 : 539.58 = 225.21 : x - Step 2: Convert to fraction form
390.99/539.58 = 225.21/x - Step 3: Cross multiply
390.99x = 539.58 × 225.21 - Step 4: Simplify right side
390.99x = 121,518.81 - Step 5: Solve for x
x = 121,518.81/390.99 - Step 6: Final answer
x = 310.80
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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.