Ideal timeline of the dance routine = 4 minutes = 4 × 60 seconds = 240 seconds
Variation allowed in the dance routine timeline = +- 5 seconds
Let the timeline of the dance routine be T
⇒ 240 seconds - 5 seconds < T < 240 seconds + 5 seconds
⇒ 235 seconds < T < 245 seconds
⇒ 
minutes < T < 
minutes
⇒ 3.92 minutes < T < 4.08 minutes
So the least possible time of the dance routine can be 3.92 minutes (or 235 seconds) and the greatest possible time of the dance routine can be 4.08 minutes (or 245 seconds)
2.5 pounds of apples * $1.20 = $3
He spent total $4.50
So he had to have spent 1.50 on oranges.
So $1.50=$1.20 x where x will be the pound of oranges bought.
1.50/1.20 = 1.25 or 1 1/4 pounds of oranges.
Let d = number of dimes, q = number of quarters
<span>Sally has 20 coins in her piggy bank, so </span>
<span>d + q = 20 </span>
<span>The total amount of money is $3.05. </span>
<span>Use the value of each coin multiplied by its number to get total value </span>
<span>.10d + .25q = 3.05 </span>
<span>multiply everything by 100 to clear the decimal places </span>
<span>10d + 25q = 305 and </span>
<span>d + q = 20 </span>
<span>solve the second equation above in terms of either d or q - lets do d </span>
<span>d = 20 - q </span>
<span>sub that into the first equation </span>
<span>10d + 25q = 305 </span>
<span>10(20 - q) + 25q = 305 </span>
<span>200 - 10q + 25q = 305 </span>
<span>15q = 105 </span>
<span>q = 105/15 = 7 </span>
<span>and from above </span>
<span>d = 20 - q = 20 - 7 = 13 </span>
<span>so, there are 13 dimes and 7 quarters </span>
<span>verify with orig problem </span>
<span>13 + 7 = 20, OK, and $1.30 + $1.75 = $3.05
</span>
Team A: 15 points
Team B: 3 points
Team A has twelve more points than Team B:
A = B + 12
Team A has five times as many points as Team B:
A = B × 5
A = 5B
substitute "A" with "B + 12" to solve for B:
A = 5B
(B + 12) = 5B
B + 12 = 5B
12 = 5B - B
12 = 4B
3 = B
Team B has 3 points
now substitute "B" with 3 to solve for A:
A = 5B
A = 5(3)
A = 15
Team A has 15 points
Check your answer by inputting both values into either equation:
A = 5B
(15) = 5(3)
15 = 15 ✔
A = B + 12
(15) = (3) + 12
15 = 15 ✔
42+30= 72
6 (36+24)=120 not equal
7 (6+30)=252 not equal
6 (7+5)=72 equal
5 (37+35)= 360 not equal
