Answer : the amount of sales tax charged is directly proportional to the amount of the purchase. anna pays $3.90 sales tax on a $60 purchase. what is the rate of the sales tax? what would the sales tax be on a $340 purchase?

6.5%

$22.10

Step-by-step explanation:

percent = part/whole * 100%

percent = $3.90/$60 * 100%

percent = 6.5%

The percent rate of the sales tax is 6.5%.

part = percent * whole

6.5% of $340 =

= 6.5% * $340

= 0.065 * $340

= $22.10

The tax on $340 is $22.10

the answer is 0.071

good luck! : d

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

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