Answer:
x=81
Step-by-step explanation:
all triangles = 180 degrees
180 - 18 = 162
162/2 = 81
81 is your answer
Answer:
yes
Step-by-step explanation:
6V + 2(V+12) = 488
8V = 464
V = 58 mph for 6 hours
V+12=70 mph for 2 hours.
check: 58*6 = 348
70*2 = 140
348 +140 =488
the car was traveling at 70 mph on the 2nd highway
Answer:
86%
Step-by-step explanation:
Let g represent the mean mark for the 10 girls in the class. Then the mean mark for the class was ...
10g +20(62%) = 30(70%)
g = 3(.7) -2(.62) . . . . . . . . . divide by 10 and subtract 2(.62)
g = .86 = 86%
The mean mark for girls was 86%.
_____
You can do this in your head if you consider it in terms of deviations from the mean. The second equation above can be rewritten and factored as ...
g = 70% +2(70% -62%)
That is, because there are 2 boys for every girl, the girl's score is above the mean by an amount that is 2 times the amount that the boy's score is below the mean. The boys' score is below by 8%, so the girls' score is above by 16%, so is 86%.
Answer: The dryer cost $375.
Step-by-step explanation:
676 - 74 = 602
602/2 = 301
301 + 74 = 375
