4. 8+12=20
4 (2+3)
First you add 2+3 and get 5
Next, since the 5 is now in the parentheses, it indicates that you have to multiply
Finally, 5 times 4=20
Answer: 2 minutes
Step-by-step explanation:
Given the following :
Plane A's descent :
y = -2,500x + 14,000
Plane B's Ascent :
y = 4,000x + 1,000
where y = altitude x = minute
Time to be at the same altitude :
Being at the same altitude means ;
Plane A's descent = Plane B's Ascent
-2,500x + 14,000 = 4,000x + 1,000
-2500x - 4000x = 1000 - 14000
-6500x = - 13000
x = 13000 / 6500
x = 2
x = 2minutes.
Answer:
add, subtract, multiply and divide complex numbers much as we would expect. We add and subtract
complex numbers by adding their real and imaginary parts:-
(a + bi)+(c + di)=(a + c)+(b + d)i,
(a + bi) − (c + di)=(a − c)+(b − d)i.
We can multiply complex numbers by expanding the brackets in the usual fashion and using i
2 = −1,
(a + bi) (c + di) = ac + bci + adi + bdi2 = (ac − bd)+(ad + bc)i,
and to divide complex numbers we note firstly that (c + di) (c − di) = c2 + d2 is real. So
a + bi
c + di = a + bi
c + di ×
c − di
c − di =
µac + bd
c2 + d2
¶
+
µbc − ad
c2 + d2
¶
i.
The number c−di which we just used, as relating to c+di, has a spec
Answer: 25% of 80 = 20
Step-by-step explanation:
(25:100)*80 =
(25*80):100 =
2000:100 = 20
- R3KTFORGOOD ☕
So these are decmials of the accutal total so
.32=32%
what makes this question easy is that there are 200 members so to convert the percents into accutall numbers so like .32=32%=64 people (since 200 is 2 times of 100)
A. fiction of 31-40 compared to 21-30
fiction 31-40=.38=38%=76 readers
fiction 21-30=.32=32%=64 readers
76-64=12
A is FALSE
B. so we want to know how many people are 31-40 and prefer fiction
so .38=38% and 38% of 200=76
B is FALSE
C 43 members are 21-30
so we look at the total row for the 21-30 people and see that .43 or 43% or 86 people are in the 21-30 age group
C is FALSE
D. 140 members prefer fiction
look at the total column for fiction and see that .70 like fiction .70=70%=140 people
D is TRUE
so A,B,C are FALSE
D is TRUE
