Hola!
Percentage Error is a measurement of the discrepancy between an observed and a true, or accepted value.
[ refer the attachment. ]
According to Question,
% error =

× 100
= 2.631 % = 2.7 % (approximately.)
hope it helps!
10^9 giga, 10^6 mega, 10^3 kilo, 10^-3 milli, 10^-6 micro, 10^-9 nano, 10^-12 pico
Potentially they might want centi which is 10^-2
Calculate force of each car:
P1 = 900 kg x 12m/s = 10,800
P2= 600 x 24 = 14,400
Degree of travel = arctan(14,300/10800)
Degree of travel = 53.1 N of E