Answer: 112
Step-by-step explanation:
Given : Significance level : 
Critical value: 
Margin of error : E = 9%=0.09
The estimated proportion of caret : p =0.38
Now, the formula to find the sample size :-
i.e. 
Hence, the required minimum sample size = 112
Answer:
-3/8
Step-by-step explanation:
PemDas
2/3 x 3/4= 1/2
3/4 x -1/2 = -3/8
full equation is now
1/2 - 1/2 + -3/8
1/2-1/2 =0
-3/8 remains
That would be first option since he did use the inverse of subtraction and added 4.5.
Insha's work is incorrectly because -4.5 + (-4.5) will not cancel each other out. It's supposed to be -9, then she should add 9 to cancel -9 out and she would have gotten 3.
Final answer: A
Hope this is clear.
Answer:
Step-by-step explanation:
The motorist drove at a distance of 90km at a constant speed for the first 40km, and then 20 km/hr faster for the rest of the journey.
The whole journey took him 1hr.
Let S denotes the average speed (in km/hr) for the first 40 km.
Hence we get the following relation,
40/S + (90 - 40)/(S + 20) = 1
or 50/(S + 20) = 1 - 40/S = (S - 40)/S
or (S + 20)(S - 40) = 50S or S^2 - 70S - 800 = 0 or (S - 80)(S + 10) = 0
or S = 80 (km/hr) [Ans]
[S cannot be negative value]
