Home / 990.20-1,485.28-296.87

Finding the Fourth Proportional to 990.20, 1,485.28 and 296.87

Calculator

Solution

The fourth proportional to 990.20, 1,485.28 and 296.87 is: 445.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    990.20 : 1,485.28 = 296.87 : x
  2. Step 2: Convert to fraction form
    990.20/1,485.28 = 296.87/x
  3. Step 3: Cross multiply
    990.20x = 1,485.28 × 296.87
  4. Step 4: Simplify right side
    990.20x = 440,935.07
  5. Step 5: Solve for x
    x = 440,935.07/990.20
  6. Step 6: Final answer
    x = 445.30

Related Problems

Find fourth proportional to 495.10, 742.64 and 148.44
Half scale
Find fourth proportional to 1,980.40, 2,970.56 and 593.74
Double scale
Find fourth proportional to 991.20, 1,486.78 and 297.87
Similar ratio
Find fourth proportional to 1,485.30, 2,227.92 and 445.31
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.