Think:
7:55 a.m. is 5 minutes (5/60 hrs) before 8 a.m.;
from 8 to noon it's 4 hours, and from noon to 2:40 p.m. is 2 2/3 hours.
Thus, you're in school 5/60 hrs + 4 hrs + 2 2/3 hrs, or
6 2/3 hrs + 5/60 hrs, or 6 40/60 hrs + 5/60 hrs, or
6 45/60 hrs, or 6 3/4 hrs.
Of course there are other ways in which you could do this problem:
4 hrs 5 min plus 2 hrs 40 min comes out to 6 hrs 45 min, or 6 3/4 hrs.
Answer:
20. AB = 42
21. BC = 28
22. AC = 70
23. BC = 20.4
24. FH = 48
25. DE = 10, EF = 10, DF = 20
Step-by-step explanation:
✍️Given:
AB = 2x + 7
BC = 28
AC = 4x,
20. Assuming B is between A and C, thus:
AB + BC = AC (Segment Addition Postulate)
2x + 7 + 28 = 4x (substitution)
Collect like terms
2x + 35 = 4x
35 = 4x - 2x
35 = 2x
Divide both side by 2
17.5 = x
AB = 2x + 7
Plug in the value of x
AB = 2(17.5) + 7 = 42
21. BC = 28 (given)
22. AC = 4x
Plug in the value of x
AC = 4(17.5) = 70
✍️Given:
AC = 35 and AB = 14.6.
Assuming B is between A and C, thus:
23. AB + BC = AC (Segment Addition Postulate)
14.6 + BC = 35 (Substitution)
Subtract 14.6 from each side
BC = 35 - 14.6
BC = 20.4
24. FH = 7x + 6
FG = 4x
GH = 24
FG + GH = FH (Segment Addition Postulate)
(substitution)
Collect like terms


Divide both sides by -3

FH = 7x + 6
Plug in the value of x
FH = 7(6) + 6 = 48
25. DE = 5x, EF = 3x + 4
Given that E bisects DF, therefore,
DE = EF
5x = 3x + 4 (substitution)
Subtract 3x from each side
5x - 3x = 4
2x = 4
Divide both sides by 2
x = 2
DE = 5x
Plug in the value of x
DE = 5(2) = 10
EF = 3x + 4
Plug in the value of x
EF = 3(2) + 4 = 10
DF = DE + EF
DE = 10 + 10 (substitution)
DE = 20
Lets round it to the nearest ten
A 97 ====> 100
B 118 ===> 120
C 179 ===> 180
D 5091 ==> 5090
No result yet, lets round to the nearest hindred.
A 97 ====> 100
B 118 ===> 100
C 179 ===> 180
D 5091 ==> 5100
As we can see only A give the same result when we round it to the nearest hundred and nearest ten.
Answer:
4
Step-by-step explanation:
First n(AUB)=n(E) - n((AUB)')
So n(AUB) = 40 - 6 = 34
Now all u hv to do is use the formulae,
n(AUB) = n(A) + n(B) - n(ANB)
So when u substitute above values,
34=22 + n(B) - 8
So,
n(B) = 4