True or false :
20÷4x5= 1
10+10÷2=15
6+4×5=50
12_3×2=6
81÷9+2=11

To solve, you must use order of operations. The acronym used is BEDMAS (brackets, exponents, division/multiplication, addition/subtraction), which is the order you solve in. 

F  20÷4x5
    =5x5
    =25
      
T   10+10÷2
      =10+5
      =15

F    6+4×5
      =6+20
      =26

T   81÷9+2
     =9+2
     =11