Amanda is 3 years older than Brantley and Carlos is twice as old as Amanda. The sum of their ages is 57. How old is Amanda?

15 years old

Step-by-step explanation:

Let's say Amanda's age is a, Brantley's age is b, and Carlos's age is c.

"Amanda is 3 years older than Brantley" means that a = 3 + b

"Carlos is twice as old as Amanda" means that c = 2 * a = 2a

"The sum of their ages is 57" means a + b + c = 57

We know that a = 3 + b, which can be written as b = a - 3. Substitute a - 3 in for b and 2a in for c in the equation a + b + c = 57 so that we have one variable to solve for:

a + b + c = 57

a + (a - 3) + 2a = 57

4a - 3 = 57

4a = 60

a = 15

Amanda is 15 years old.

15

Step-by-step explanation:

A = B + 3

B = A - 3

C = 2A

A + B + C = 57

A + A - 3 + 2A = 57

4A - 3 = 57

4A = 60

A = 15

i need the options

step-by-step explanation:

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!