Rectangular book
two 8 1/2 sides
two 9 1/4 sides
8 1/2*2=17
9 1/4*2=18 1/2
17+18 1/2= 35 1/2
The perimeter of the textbook is 35 1/2 inches or 35.5 inches.
Hope this helps :)
Let x be the time she ran and y be the time she walked
then distance ran = 25x and distance walked = 5y
so 15x + 5y = 42
and x + y = 4
* second equn. by -5:-
-5x - 5y = -20
add this to the first equn:0
10x = 22
x = 2.2
distance she ran = 2.2 * 15 = 33 km
1.4 because if you do your math it gives you a sum of 1.4
