Home / 307-490

Finding the Third Proportional to 307 and 490

Calculator

Solution

The third proportional to 307 and 490 is: 782.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    307 : 490 = 490 : x
  2. Step 2: Convert to fraction form
    307/490 = 490/x
  3. Step 3: Cross multiply
    307x = 490 × 490
  4. Step 4: Simplify right side
    307x = 240,100
  5. Step 5: Solve for x
    x = 240,100/307
  6. Step 6: Final answer
    x = 782.08

Related Problems

Find third proportional to 153.50 and 245
Half scale
Find third proportional to 614 and 980
Double scale
Find third proportional to 309 and 493
Similar ratio
Find third proportional to 460.50 and 735
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.60) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.