Home / 490-676-280.12

Finding the Fourth Proportional to 490, 676 and 280.12

Calculator

Solution

The fourth proportional to 490, 676 and 280.12 is: 386.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    490 : 676 = 280.12 : x
  2. Step 2: Convert to fraction form
    490/676 = 280.12/x
  3. Step 3: Cross multiply
    490x = 676 × 280.12
  4. Step 4: Simplify right side
    490x = 189,361.12
  5. Step 5: Solve for x
    x = 189,361.12/490
  6. Step 6: Final answer
    x = 386.45

Related Problems

Find fourth proportional to 245, 338 and 140.06
Half scale
Find fourth proportional to 980, 1,352 and 560.24
Double scale
Find fourth proportional to 491, 677.38 and 281.12
Similar ratio
Find fourth proportional to 735, 1,014 and 420.18
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.