Question

What is the next number? 3 6 4 8 6 12 10

Answer 1

`20`

Explanation:

The series `3, 6, 4, 8, 6, 12, 10` can be written as

`color(white)(.) underbrace(3 color(white)(...) 6) color(white)(....) underbrace(6 color(white)(...) 4) color(white)(....) underbrace(4 color(white)(...) 8) color(white)(....) underbrace(8 color(white)(...) 6) color(white)(....) underbrace(6 color(white)(...) 12) color(white)(....) underbrace(12 color(white)(...) 10)`
`×2 color(white)(....) -2 color(white)(....) ×2 color(white)(....) -2 color(white)(.....) ×2 color(white)(.......) -2 color(white)(.)`

If `chi` is the next number then

`underbrace(10 color(white)(...) chi)`
`×2`

`chi = 10 × 2 = 20`