3+6×5+4÷2-7 using the same expression, add parentheses so that the value of the expression is 38

3+6×(5+4÷2)-7  

Step-by-step explanation:

To solve the expression use order of operations.

Right now the expression solves to:

3+6×5+4÷2-7                  6* 5 = 30

3 + 30 + 4÷2-7                4 ÷ 2 = 2

3 + 30 + 2 - 7                   Add and subtract left to right.

33 + 2 - 7

35 - 7

28

To make it solve to 38, add parenthesis:

3+6×(5+4÷2)-7                (5+4÷2) = 7

3+6×(7)-7                        6*7 = 42

3 + 42 - 7                        Add and subtract from left to right

45 - 7

38

he spend 5.1 minutes chatting with his friends.

step-by-step explanation:

2/5+1/2=9/10

6/1-9/10=5.1

10/60

step-by-step explanation:

if you divide 10 by 60 the answer is 0.166666 while if you divide or solve the other problems it equals 0.6