3 1/2 +6 1/4×2 2/3#pake cara

3 1/2 + 6 1/4 × 2 2/3
= 3 1/2 + 25/4 × 8/3
= 3 1/2 + 200/12
= 3 1/2 + 16 8/12
= 3 6/12 + 16 8/12
= 19 14/12
= 20 2/12
= 20 1/6

3 1/2=7/2
6 1/4=25/4
2 2/3=8/3

25/4×8/3=200/12

200/12+7/2=200/12+42/12=242/12=20 2/12=20 1/6

semoga benar 
amin.........................