Need help ASAP. <br>what is the best estimate for the value of the expression?<br>

A mixture of 30 pounds of candy sells for $1.10 a pound. The mixture consists of chocolates worth $1.50 a pound and chocolates w

astra-53 [7]

$x-chocolate\ worth\ 1,50\$ \ per\ pound\\
y-chocolate\ worth\ 0,9\$\ per\ pound\\
\\\\
 \left \{ {{x+y=30} \atop {30*1,10=x*1,50+y*0,9}} \right.\\\\ \left \{ {{x=30-y} \atop {33=1,5x+0,9y}} \right. \\\\ Using \ substitution\ method:\\\\33=1,5(30-y)+0,9y\\\\
33=45-1,5y+0,9y\\\\ -12=-0,6y\ |:-0,6\\\\
y=20\\
x=10$

3 0

2 years ago

Is x+y^3=27 a function?

inna [77]

Yes, its a function b/c y is a function of x.

5 0

3 years ago

The sum of 3 consecutive odd numbers is 51. What is the second number in this sequence?

Veseljchak [2.6K]

Assume the second number is x, then the other two are x - 2, x + 2

So x-2 + x + x + 2 = 51

-> 3x = 51

-> x = 17

7 0

3 years ago

If a rectangle is altered by increasing its length by 20 percent and its width by 10 percent, its area increases by a percent. W

aleksklad [387]

Answer:

D

Step-by-step explanation:

Remember that the formula for the area of a rectangle is:

$A=lw$

Where l is the our length and w is our width.

If we increase our length by 20%, this means that we add 20% or 0.2 of our old length to our old length. So, our new length will be:

$l_{new}=l+.2l$

Combine like terms:

$l_{new}=1.2l$

Similarly, if we increase our width by 10%, this means that we add 10% or 0.1 of our old width to our old width. So, our new width is:

$w_{new}=0.1w+w$

Combine like terms:

$w_{new}=1.1w$

Therefore, our new area will be:

$A_{new}=(l_{new})(w_{new})$

Substitute 1.2l and 1.1w. This yields:

$A_{new}=1.2l(1.1w)$

Multiply:

$A_{new}=1.32lw$

Our old area is:

$A_{old}=lw$

So, our area increased by a factor of 1.32.

This is the same as 32% of our old area.

So, our answer is D.

And we're done!

5 0

3 years ago

Question Help Scores of an IQ test have a bell-shaped distribution with a mean of 100100 and a standard deviation of 1010. Use

3241004551 [841]

Answer:

a) 95% percentage of people has an IQ score between 80 and 120.

b) 68% percentage of people has an IQ score between 90 and 110.

c) 2.5% percentage of people has an IQ score greater than 120.

Step-by-step explanation:

The empirical formula states that:

The empirical rule is known as the three-sigma rule or 68-95-99.7 rule.
It is a rule which states that for a normal distribution, almost all data falls within three standard deviations of the mean.
68% of data falls within the first standard deviation that is $\mu \pm \sigma$