1. At the moment we (sit) .............................. in a cafe. We (wait) ..................... for the museum to open, so I (write) ............................ some postcards.

2. Miss Helen (help) ............................. as soon as she (finish) ............................. that letter.

3. Boys like (play) ............................. marbles or catch while girls enjoy (skip) .............. rope or chatting.

4. (you/ go) ....................................... abroad for your holiday? - Well, I (get) ................... a holiday job. I’m going to an agent’s on Saturday (find out) ........................... about it.

Rảnh CMN àk

Ta có

n + 4 chia hết cho n + 1

(n + 1) + 3 chia hết cho n +1 (1)

Vì n + 1 chia hết cho n + 1 (2)

Từ (1) và (2) => 3 chia hết cho n + 1

=> n + 1 E ( 1,-1,3,-3)

     n E ( 0,-2,2,-4)

k mik nha

x + 50 = 200 + 100

x + 50 = 300

x         = 300 - 50

x         = 250