432 McGRAW-HILL’S SAT
- A The revenue generated from two widgets, two
gadgets, and two tinkers is $2w,$2x,and $2(6),
respectively. The cost of producing two widgets,
two gadgets, and two tinkers is $8, $6, and $2y,
respectively. Therefore, the total profit can be
found by subtracting the cost from the revenue:
(2w+ 2 x+12) −(8 + 6 + 2 y) = 2 w+ 2 x− 2 y−2. - 86 The boys bought only sandwiches and spent
($4.50)(75) +($5.00)(80) +$3.75(22) =$820.00. If
the girls bought only sandwiches with fries, then
they spent ($5.50)(40) +($6.00)(35) +$4.75(64) =
$734.00. $820.00 −$734.00 =$86.00 - D If x=sandwiches: x(4.5) +(40 −x)(5.5) = 206
Distribute: 4.5x+ 220 −5.5x= 206
Combine like terms: −1.0x=− 14
Divide by −1: x= 14
There were (40 −x) = 40 − 14 =26 meals with fries.
Concept Review 5
- A best fit line is a straight line that “hugs” the data
most closely on a scatterplot. - It can be created by connecting the “outermost”
points on the plot or by drawing a line that best
“hugs” the points and divides them in half. Try to
ignore any outliers that don’t fit with the rest of
the data. - For the SAT, you just need to be able to tell if a
slope is positive or negative, or perhaps greater or
less than 1. Positive slopes go up to the right, and
negative slopes go down to the right. If the slope
is positive and the “rise” is greater than the “run,”
the slope is greater than 1; if the rise is less than
the run, the slope is less than 1. - If you know what percent of the data are in a sec-
tor of the pie chart, multiply the percentage by
360 °to obtain the degree measure of that sector
(e.g., a sector that represents 40% of the circle
would be (.40)(360°) = 144 °). - The biggest percent change occurs between
Thursday and Fridays.
Percent change =(100%)(10.5 −5)/(5) =110%. - There were a total of 13 + 7 + 14 + 5 + 5 +10.5 +
11.5 =66,000 accidents; 35,000 of them occurred
on Friday, Saturday, or Sunday. 35/66 =53% - 25% of the kids said blue was their favorite color.
25% of 4,000 =0.25 ×4,000 =1,000. 20% of the
kids said yellow was their favorite color. 20% of
4,000 =0.20 ×4,000 =800. 1,000 − 800 =200 kids. - The color red represents 10% of the circle, which
is 10% of 360°. °- There are currently (.25)(4,000) =1,000 votes for
blue. In order for blue to be 50% of the circle, it
would need (.50)(4,000) =2,000 votes. Therefore,
1,000 votes must change. - Hamden High ordered 36 + 28 + 81 =145 tickets.
New Haven Public ordered 64 + 23 + 64 =151.
Waterbury High ordered 53 + 31 + 51 =135. - 81 Hamden High students bought 5-day passes at
$200.00/pass, spending (81)(200) =$16,200. 64
students at New Haven Public bought 5-day
passes at $200/pass, spending (64)(200) =$12,800.
The difference is $16,200 −$12,800 =$3,400.
10 360
100
36
( )
=
Answer Key 5: Data Analysis
SAT Practice 5
- B A line connecting (32, 6.5) and (39.5, 8.0) is a
good line of fit, and has a slope of 1.5/7.5 =0.2,
which is between 0 and 1. - C If the slope is about 0.2, you can use the slope
equation to solve:Plug in values:Simplify:Multiply by 4: (6.5 −y 1 ) =0.8
Subtract 6.5: −y 1 =−5.7
Divide by −1: y 1 =5.7- C From March to April: 30 − 15 =15,000
From April to May: 30 − 30 = 0
From May to June: 60 − 30 =30,000
From June to July: 65 − 60 =5,000
From July to August: 69 − 65 =4,000
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