Answer:
The number of children are 4 out of which 3 are girls
Step-by-step explanation:
Data provided in the question:
P(Two randomly selected children are girls) = 
now,
let the number of children be 'n'
the number of girls be 'x'
thus,
P(Two randomly selected children are girls) = 
=
also,
= 
thus,
=
or
=
or
2x(x-1) = n(n-1)
now
for x = 3 and n = 4
i.e
2(3)(3-1) = 4(4-1)
12 = 12
hence, the relation is justified
therefore,
The number of children are 4 out of which 3 are girls
Answer:
x^2 -81
Step-by-step explanation:
(x+9)(x-9)
FOIL
first x*x = x^2
outer -9x
inner 9x
last -9*9 = -81
Add them together
x^2 -9x+9x -81
Combine like terms
x^2 -81
Answer:
Sum is - 5n² -8n + 4.
Step-by-step explanation:
Given : (3n² – 5n + 6) + (–8n²– 3n – 2) .
To find : Sum .
Solution : We have (3n² – 5n + 6) + (–8n²– 3n – 2) .
Combine like terms :
(3n² - 8n²– 5n - 3n + 6 - 2).
- 5n² -8n + 4.
Therefore, Sum is - 5n² -8n + 4.
Answer:
170
270
271
371
372
370
470
471
473
472
574
573
572
571
570
675
674
673
672
671
670
776
775
774
773
772
771
770
877
876
875
874
873
872
871
870
978
977
976
975
974
973
972
971
970
Step-by-step explanation:
