4) If x/y = 7/3 then find the value of
​

1011

Step-by-step explanation:

3x^2 + 2y^2 x^2 - 2y^2

3(7)^2 + 2(3)^2 3^2 - 2(7)^2

3(7^2 + 2 x 3 x 7^2 - 2 x 3)

3(7^2 +6 x 7^2 - 6)

3(7 x 7^2 - 6)

3(7^3 - 6)

3(343 - 6)

3(337) = 1011

​

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

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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