Home / 280-399.50

Finding the Third Proportional to 280 and 399.50

Calculator

Solution

The third proportional to 280 and 399.50 is: 570.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    280 : 399.50 = 399.50 : x
  2. Step 2: Convert to fraction form
    280/399.50 = 399.50/x
  3. Step 3: Cross multiply
    280x = 399.50 × 399.50
  4. Step 4: Simplify right side
    280x = 159,600.25
  5. Step 5: Solve for x
    x = 159,600.25/280
  6. Step 6: Final answer
    x = 570.00

Related Problems

Find third proportional to 140 and 199.75
Half scale
Find third proportional to 560 and 799
Double scale
Find third proportional to 282 and 402
Similar ratio
Find third proportional to 420 and 599.25
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.43) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.