Answer:
Step-by-step explanation:
B
its B
Answer:
B 8.56
this is the answer because you simply add what he bought so 1.13+1.13+1.76 which is 4.02 then subtract what he started with which was 12.58 so 12.58-4.02 is 8.56 so that's your answer
Sand to cement
7:3
210:x
ask yourself what number is needed to multiply by 7 to get 210 ( so you'd divide 210 by 7 which is 30). Multiply the other side by thirty as well to get the value of x
3*30 which is 90
Answer:
the lower right matrix is the third correct choice
Step-by-step explanation:
Your problem statement shows that you have correctly selected the matrices representing the initial problem setup (middle left) and the problem solution (middle right).
Of the remaining matrices, the upper left is an incorrect setup, and the lower left is an incorrect solution matrix.
__
We notice that in the remaining matrices on the right that the (2,3) term is 0, and the (3,2) and (3,3) terms are both 1.
The easiest way to get a 0 in the 3rd column of row 2 is to add the first row to the second. When you do that, you get ...
![\left[\begin{array}{ccc|c}1&1&1&29000\\1+2&1-3&1-1&1000(29+1)\\0&0.15&0.15&2100\end{array}\right] =\left[\begin{array}{ccc|c}1&1&1&29000\\3&-2&0&30000\\0&0.15&0.15&2100\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Cc%7D1%261%261%2629000%5C%5C1%2B2%261-3%261-1%261000%2829%2B1%29%5C%5C0%260.15%260.15%262100%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Cc%7D1%261%261%2629000%5C%5C3%26-2%260%2630000%5C%5C0%260.15%260.15%262100%5Cend%7Barray%7D%5Cright%5D)
Already, we see that the second row matches that in the lower right matrix.
The easiest way to get 1's in the last row is to divide that row by 0.15. When we do that, the (3,4) entry becomes 2100/0.15 = 14000, matching exactly the lower right matrix.
The correct choices here are the two you have selected, and <em>the lower right matrix</em>.
If you want to easily find the solution you can use your calculator.
Just divide 77 by 110 and see the result.
77/110 = 0.7 = 7/10 = 70/100 = 70%
100% - 70% = 30%
Explanation
110*x=77
x=77/110, but the answer is not a percent
So 77/110 = ?/100 => ?=77*100/110=70 => 70%
But since 70% does not represent a percentage decreasement, we need to subtract it from the 100%
100% - 70% = 30%