Answer:
Carter family = 25 hours
Davis family = 31 hours
Step-by-step explanation:
Let's say the number of hours the Carter family used their sprinkler is x and the number of hours the Davis family used their sprinkler for is y.
So combined:
x + y = 45 hours
and we are also told that:
40x + 15y = 1300 L
So we can do simultaneous equations to solve the problem.
With some rearranging, we can figure out that:
y= 45 - x
and by substituting that into the second equation:
40x + 15 (45 -x) = 40x + 675 - 15x = 1300L
25x = 1300 - 675
25x = 625
x = 25 = hours that the Carter family used their sprinkler
and we can substitute that back into the original equation to find how many hours the Davis family used their sprinkler so:
25 + y = 56
y = 31
The Davis family used their sprinkler for 31 hours whilst the Carter family used their sprinkler for 25 hours.
Answer:
To solve an exponential equation, take the log of both sides, and solve for the variable.
Step-by-step explanation:
Example 1: Solve for x in the equation tex2html_wrap_inline119 .
Solution:
Step 1: Take the natural log of both sides:
displaymath121
Step 2: Simplify the left side of the above equation using Logarithmic Rule 3:
displaymath123
Step 3: Simplify the left side of the above equation: Since Ln(e)=1, the equation reads
displaymath127
Ln(80) is the exact answer and x=4.38202663467 is an approximate answer because we have rounded the value of Ln(80)..
Check: Check your answer in the original equation.
displaymath131
Yes you are right! There is much more balance in the left than in the right!
The cost of the 9th item is $3.94
Since the mean cost for the 9 items in his bag was $2.71. Then, the total cost will be: = 9 × $2.71 = $24.39
In order to get the price of the 9th item, we have to calculate the price of all the 8 items given which will be:
$2.01 + $2.20 + $2.68 + $3.59 + $3.12 + $1.64, + $1.75 + $3.46 = $20.45
Therefore, the cost of the 9th item will be:
= $24.39 - $20.45
= $3.94
Read related link on:
brainly.com/question/24562826
Answer:
.........................
