Answer:
About <em>4 hours.</em>
Step-by-step explanation:
To find the answer we will <em>add both percentages</em> of <u><em>Watching TV</em></u> and <u><em>Homework</em></u>. 8% + 13% = <em>21%</em>. Now we will <em>divide 100 by 21</em> and we get<em> 4 hours a day.</em>
Answer:
11
Step-by-step explanation:
The two equations appear to be ...
- 12x +4y = 152
- 32x +12y = 420
These can be solved for y using Cramer's rule:
y = (152(32) -420(12))/(4(32) -12(12)) = -176/-16 = 11
The cost of the vegetarian lunch is 11.
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<em>Comment on Cramer's Rule</em>
For equations ...
ax +by =c
dx +ey = f
The solutions are ...
x = (bf -ey)/(bd -ea)
y = (cd -fa)/(bd -ea) . . . . note the denominators are the same expression
Once you memorize the pattern of products, this can be the simplest way to solve a pair of equations--especially if you only need one of the variable values.
32 if you fold it 4 times and times that by 2 it will be 32