Equation is y=kx. We have four chance to figure out k; hopefully they all give the same result
x=9, y=63, y=kx becomes 63=k(9) so k=63/9=7
x=4, y=28, 28=k(4), k=7
The constant of proportionality is 7; we check 2×7=14, 11×7=77
Answer: k=7, y=7x
X/y = 2 so x = 2y
z/x = 4 so z = 4x but x = 2y so z = 4(2y) = 8y
now you have
x = 2y, z = 8y
x + y + z 2y + y + 8y 11y 11
------------ = -----------------------= ------------- = ----------- = 5 1/2
x 2y 2y 2
answer
C. 5 1/2
Hello,
The two lights flash at the same time every 18 min
at 8:00 h=480 min =480+0*36
at 8:36 h=516 min =480+1*36
...
54 is not divisible by 36
60+12=72 = 2*36 yes
60+24=84 not
120+24=4*36 yes
180+18=198 not
So 2 times are correct 9:12 and 10:24
Answer G