Devon is buying 3 greeting cards that cost $0.97 each. How can rounding be used to estimate the total cost of the cards? Since each card is about $1, the total cost is approximately 3 + 1 = $4. Since each card is about $1, the total cost is approximately 3 × 1 = $3. Since he is buying about 10 cards, the total cost is approximately 10 × 0.97 = $9.70. Since he is buying about 10 cards, the total cost is approximately 10 + 0.97 = $10.97.

the final amount you will pay is $68.04.

the tip is determined by the pre-tax amount, so we calculate the tip based on the original bill, not after we've added sales tax.

to find the tip:

we can divide 54.00 by 100 to get 1% of 54. then we multiply that by 18.

54 / 100 = .54

.54 x 18 = 9.72

tip = 9.72$

to find the tax:

we can divide 54.00 by 100 to get 1% of 54. then we can multiply that by 8 to get 8%.

54 / 100 = .54

.54 x 8 = 4.32

tax= 4.32

now we can add the tip and tax to the bill to get our total.

54 + 9.72 + 4.32 = 68.04

total: $68.04

step-by-step explanation:

the answer is:

the correct option:

b.

to solve the problem, we need to remember how to operate to simplify exponential expressions using the logarithms.

we are given the equation:

then, using placing logarith with base 7 on both sides of the equation, we have:

so, rounding the obtained result to two decimal places (nearest hundreth), we have:

hence, we have that the correct option:

b.

have a nice day!

step-by-step explanation:

infinity is the answer