When doing multiple operations, always remember PEMDAS. There is division and addition. D comes first and is the division so we do that first followed by addition. So we have $\displaystyle 4+6\div2=4+3=7$. 

When doing multiple operations, always remember PEMDAS. There is division and multiplication but parantheses present. P is parantheses and always has priority over every operation. So let's work the math inside the parantheses. So we have $\displaystyle (4*3)\div (6*2)=12\div12=1$. 

When doing multiple operations, always remember PEMDAS. There is division and subtraction. D is division and has priority over subtraction.  So we have $\displaystyle 68\div17-9\div3=4-3=1$. 

When doing multiple operations, always remember PEMDAS. There is exponents and subtraction. E is exponents and has priority over subtraction.  So we have $\displaystyle 7^2-12=49-12=37$. 

When doing multiple operations, always remember PEMDAS. There is parentheses, exponents, multiplication, addition, and subtraction. We will work the parentheses first, follow by exponent thenaddition, then multiplication, and finally subtraction.  So we have $\displaystyle 6-5(4^2+3)=6-5(16+3)=6-5(19)=6-95=-89$. 

When doing multiple operations, always remember PEMDAS. There are parantheses, exponents, multiplication, addition and subtraction. We will do the parantheses first, then exponents, then multiplication, addition and last subtraction.  So we have $\displaystyle 5+(3*4^2-3)=5+(3*16-3)=5+(48-3)=5+45=50$. 

When doing multiple operations, always remember PEMDAS. There is addition and subtraction and they are grouped together as last priority. So we just do the operations from left to right. $\displaystyle 3+4=7$

$\displaystyle 7-5=2$. Answer is $\displaystyle 2$. 

When doing multiple operations, always remember PEMDAS. There is division and multiplication. They are grouped together is third priority. So must work from left to right.

$\displaystyle 3\ast4=12$

$\displaystyle 12\div2=6$

$\displaystyle 6\ast6=36$

The answer is $\displaystyle 36$. 

When doing multiple operations, always remember PEMDAS. There is addition and multiplication but parantheses present. There is multiplication because the $\displaystyle 3$ connected to the parantheses represents multiplying in which the sign doesn't need to be present. It is meant to be distributed. P is parantheses and always has priority over every operation. So let's work the math inside the parantheses. So we have $\displaystyle (4+5)3+7=(9)3+7=27+7=34$. 

When doing multiple operations, always remember PEMDAS. We have parenthesis, exponents, multplication, and division. We will do the parenthesis first followed by exponents and multiply and divide from left to right. So we have $\displaystyle 4(3^2-7)\div2*17=4(9-7)\div 2*17=4(2)\div 2\ast 17=8\div2*17=4*17=68$.