Notice that
13 - 9 = 4
17 - 13 = 4
so it's likely that each pair of consecutive terms in the sum differ by 4. This means the last term, 149, is equal to 9 plus some multiple of 4 :
149 = 9 + 4k
140 = 4k
k = 140/4
k = 35
This tells you there are 35 + 1 = 36 terms in the sum (since the first term is 9 plus 0 times 4, and the last term is 9 plus 35 times 4). Among the given options, only the first choice contains the same amount of terms.
Put another way, we have
but if we make the sum start at k = 1, we need to replace every instance of k with k - 1, and accordingly adjust the upper limit in the sum.
No solutions
Explanation: Any number you use, the equation of x + 7 will always be 2 more than x + 5
Answer: Natalie make $ 367.5 in a week in which she made $225 in sales .
Natalie make $ ( 300+x ) in a week in which she made $ x in sales .
Step-by-step explanation:
Base Salary of Natalie = $300
Also, she gets 30% of the her total sales for the week.
If total sales in a week = $225
commission = 30% of $225
= $ ( 0.30 × 225)
= $ 67.5
Natalie got = Base Salary + Commission
= $300 + $ 67.5
= $ 367.5
∴ Natalie make $ 367.5 in a week in which she made $225 in sales .
If total sales in a week = $x
commission = 30% of $x
= $ ( 0.30 × x)
= $ 0.30 x
Natalie got = Base Salary + Commission
= $ ( 300+x )
∴ Natalie make $ ( 300+x ) in a week in which she made $ x in sales .
It’s A
As it says in the answer, you usually add / subtract the exponents when needed.
