The mean mass of the 15 players in a rugby team is 85.2kg the mean mass of the team plus a substitute is 85.4kg what is the mass of the substitute ?

88.4 kg

Step-by-step explanation:

Since we are given the mean we will need to multiply the mean by how many players there are on the team to find the total mass. (The second mean will be multiplied by 16 because it is the number of players on the team plus the substitute)

85.2 x 15 = 1,278

85.4 x 16 = 1,366.4

Subtract the first mass from the second because this will remove the mass of the 15 other players.

1366.4 - 1278 = 88.4

88.4 kg is the mass of the substitute.

step-by-step explanation: so we look at the formula un = a + (n-1)d

un is the amount of seats

n is the nth term aka row number

a is the original sequence/row number

d is the difference between each term

so in this a=22 d=6 and n can remain as n because we are simply formjng a rule

lets put these in the equation

un=22+(n-1)(6)

this is your answer to part a

however

lets double check that this is correct, we'll try putting it into the second term

un=a+(n-1)d

u2=22+(2-1)(6)

u2=22+6

u2=28

as the question said the second row has 28 seats so now we know the formula we made is correct.

as for part b

un=a+(n-1)

its asking us to find a row with 100 seats.

remember un was the amount of seata so all we do is substitute this in.

un=100 a=22 d=6

un=a+(n-1)d

100=22+(n-1)(6)

so now we simplify to find n which is the row number.

100-22=22+(n-1)(6)-22

78=(n-1)(6)

78/6=(n-1)(6)/6

13=n-1

13+1=n-1+1

14=n

so now we know that in the 14th row there is 100 seats.

hope this and that you understood! its my first time using the app or anyone out on here : p its also me to revise so a bunch! ask more questions if you dont understand ☺

after going and makeing graphs i would go with a,

there is nothing that is matches the graph. if there was i would show you. but therefore my answer is a.

hope i

-lavira: )