Home / 319-440.42-208.78

Finding the Fourth Proportional to 319, 440.42 and 208.78

Calculator

Solution

The fourth proportional to 319, 440.42 and 208.78 is: 288.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    319 : 440.42 = 208.78 : x
  2. Step 2: Convert to fraction form
    319/440.42 = 208.78/x
  3. Step 3: Cross multiply
    319x = 440.42 × 208.78
  4. Step 4: Simplify right side
    319x = 91,950.89
  5. Step 5: Solve for x
    x = 91,950.89/319
  6. Step 6: Final answer
    x = 288.25

Related Problems

Find fourth proportional to 159.50, 220.21 and 104.39
Half scale
Find fourth proportional to 638, 880.84 and 417.56
Double scale
Find fourth proportional to 320, 441.80 and 209.78
Similar ratio
Find fourth proportional to 478.50, 660.63 and 313.17
1.5x scale

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.