Sometimes in mental arithmetic, calculations are done in a different order because the numbers are more "convenient." For example,
consider the following calculations:
13.2.5 = 26.5 = 130
and
calculations. However, the
13.2.5 = 13 - 10 = 130
The first calculation was performed left-to-right, according to the standard rule for several multiplicati
second calculation is much simpler because it was done in a different order.
Which of the following mathematical properties allows us to do this?
The associative property of multiplication
The commutative property of addition
The associative property of addition
The commutative property of multiplication

(a×b)×c=a×(b×c)

This means that multiplication is associative.

The associative property of multiplication

3; 9 is 8 to -4

step-by-step explanation:

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 ☺