The ratio fo boys to girls is 12:16
Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used
Answer:
Step-by-step explanation:
(35 - 20)/20
15/20 = .75
.75 * 100 == 75%
75%
Answer:
see explanation
Step-by-step explanation:
To verify cos²A + sin²A = 1 with A = 90° , then
cos²90° + sin²90°
= (0)² + (1)²
= 0 + 1
= 1
