Answer:
Step-by-step explanation:
we know that
The simple interest formula is equal to
where
I is the Final Interest Value
P is the amount of money borrowed
r is the rate of interest
t is Number of Time Periods
in this problem we have
substitute in the formula above
The order of arithmetic operations is given by the acronym PEMDAS, which means
Parentheses,
Exponents,
Multiplication,
Division,
Addition,
Subtraction.
These two examples illustrate how the use of parentheses can change the order.
Example 1:
5+7/3x4-2/5 has an answer of 13.933.
Use PEMDAS to obtain
5+(7/3)x4-(2/5)
= 5+(2.3333x4)-0.4
= 5+9.3333-0.4
= 14.3333-0.4
= 13.933
If we apply the parentheses: (5+7)/3x4-2/5
The result is
(12/3)x4-(2/5)
= (4x4)-0.4
= 16-0.4
= 15.06
which is a different answer.
Example 2:
8/3²x5+4 has the answer 8.444
Use PEMDAS to obtain
8/(3²)x5+4
= (8/9)x5+4
= (0.8889x5)+4
= 4.4444+4
= 8.4444
If we apply the parentheses (8/3)²x5+4:
The result is
2.6667²x5+4
= 7.1113x5+4
= 35.5565+4
= 39.5565
which is a different answer.
Answer: She should blend 98 lbs of high-quality beans.
She should blend 72 lbs of cheaper beans
Step-by-step explanation:
Let x represent the number of pounds of high quality beans that she should blend.
Let y represent the number of pounds of cheaper beans that she should blend.
She needs to prepare 170 lbs of blended coffee beans. This means that
x + y = 170
She plans to do this by blending together a high-quality bean costing $4.75 per pound and a cheaper bean at $2.00 per pound. The blend would sell for $3.59 per pound. This means that the total cost of the blend would be 3.59×170 = $610.3. This means that
4.75x + 2y = 610.3 - - - - - - - - - -1
Substituting x = 170 - y into equation 1, it becomes
4.75(170 - y) + 2y = 610.3
807.5 - 4.75y + 2y = 610.3
- 4.75y + 2y = 610.3 - 807.5
- 2.75y = - 197.2
y = - 197.2/-2.75 = 71.9
y = 72 pounds
x = 170 - y = 170 - 71.9
x = 98.1
x = 98 pounds
last one. i can do the first part. put x = distance from top of ladder to the floor, y = distance from base of ladder to the wall (draw a picture) then pythagoras sez
<span><span>x2</span>+<span>y2</span>=25</span>
calculus says
<span>2x<span>x′</span>+2y<span>y′</span>=0</span>
and you are told that
<span><span>y′</span>=2</span>
so you know
<span>2x<span>x′</span>+4y=0</span>
or
<span><span>x′</span>=−<span><span>2y</span>x</span></span>
