Answer:
740
Step-by-step explanation:
The n th term of an arithmetic series is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₃ = 7 and a₇ = (3 × 7) + 2 = 21 + 2 = 23 , then
a₁ + 2d = 7 → (1)
a₁ + 6d = 23 → (2)
Subtract (1) from (2) term by term
4d = 16 ( divide both sides by 4 )
d = 4
Substitute d = 4 into (1)
a₁ + 2(4) = 7
a₁ + 8 = 7 ( subtract 8 from both sides )
a₁ = - 1
The sum to n terms of an arithmetic series is
=
[ 2a₁ + (n - 1)d ] , thus
=
[ (2 × - 1) + (19 × 4) ]
= 10(- 2 + 76) = 10 × 74 = 740
13 x 3=39
70 x 3= 210
After 38 years there will be foxes. ( Type a whole number.)
Answer:
170 square feet
Step-by-step explanation:
Answer:
2 people
Step-by-step explanation:
Total number of people (n) = 50
Borderlands II (B) = 20
Fortnite (F) = 33
Minecraft (M) = 19
Borderlands and Fortnite (B&F) = 15
Borderlands and Minecraft (B&M)= 10
All games (B&M&F) = 5
The number of people that claimed more than one game as their favorite (X) is given by:

Those people can be divided in B&F only, B&M only, M&F only and B&M&F:

7 people claimed that Minecraft and Fortnite were their favorites however, 5 of those people claimed all of the games as their favorite. Therefore, only 2 people declared Minecraft and Fortnite (exclusively) as their favorites.