The formula for perimeter is P = 2length + 2width (P = 2L + 2W)
In this case:
Length = 5 in
Width = 10 in
Plug what you know into the perimeter formula:
P = 2(5) + 2(10)
OR
P = 2 × 5 + 2 × 10
To solve this you must use the rules of PEMDAS (Parentheses, Exponent, Multiplication, Division, Addition, Subtraction)
First we have multiplication. Remember that when solving you must go from left to right
P = 2 × 5 + 2 × 10
2 × 5 = 10
P = 10 + 2 × 10
2 × 10 = 20
P = 10 + 20
Now we have addition:
P = 10 + 20
P = 30
The perimeter of this book is 30 inches
Hope this helped!
~Just a girl in love with Shawn Mendes