Which of these equations correctly represents the following scenario: In her prime, 40 million people knew who Britney Spears was, but that number has been decreasing by 10% each year. So, since 90% of people still recognize her each year, how many people still know who Britney is each year?

y = 40,000,000(0.9)x

y = 0.9(40,000,000)x

y = 40,000,000(0.01)x

y = 0.1x + 40,000,000

y = 0.01(40,000,000)x

Its the first option

40,000,000(0.9)x.

Step-by-step explanation:

90% recognise her each year so after 1 year so the number (N) is:

N = 40,000,000(0.90)^1 = 36,000,000 recognise her after 1 year.

N = 40,000,000(0.90)^2 = 32,400,000 recognise her after 2 yeas

- and so on.

After x years:

N = 40,000,000(0.90)^x.  

Note the x is a power and is best written as ^x.

phosphate, calcium ion, chloride ion, neon atom

step-by-step explanation:

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads