Algebra 1 Common Core Student Edition, Grade 8-9

38. Rounding Error Your science class visits an aquarium. In a
    re p o rt o n your class’s visit, you sketch one of th e fish tanks an d
    ro u n d th e dim ensions as show n in the diagram at th e right.
    You use th e ro u n d e d d im ensions to state th e ta n k ’s volum e
    is approxim ately (7 m )(5 m )(3 m ) = 105 m3. W hat is the
    p ercen t error in your volum e calculation due to rounding?


39. St udent Discount s You show your s tu d en t identification at a local re sta u ran t in
    order to receive a 5% discount. You s p en d $12 for your m eal at th e restaurant. How
    m uch w ould your m eal cost w ithout the discount?
    4^ Ch a l l e n g e 4 0. Geo m et r y The height of a cylinder is 2 ft. The d iam eter of th e base is 5 ft. Each
    dim ension is accurate to th e n ea rest foot. W hat is th e greatest possible error in
    calculating th e volum e of th e cylinder? Use 3.14 for tt.


40. a. The sides of a square th at m easures 4 m by 4 m increased in length by 10%. Find
    th e p ercen t of increase in th e area.
    b. The sides of a square th at m easures 6 m by 6 m increased in length by 10%. Find
    th e p ercen t of increase in th e area.
    c. Reaso n i n g Predict th e p ercen t of increase in th e area of a square th a t m easures
    8 m by 8 m if th e side lengths increase by 10%. Explain a n d check your answer.

r \
St a n d a r d i ze d Test Pr ep

^SAT/ACT 42. M arcus bought a shirt th a t was m arked $28, b u t it was on sale for 15% off the

m arked price. W hat was th e price of th e shirt after th e discount?

C O $4.20 G D $23.80 C O $24.80 C O $32.20

43. W hat equation do you get w hen you solve a x + bx = c for x?
    CO x = c - ab CO x = c - a - b CO x = —zruat) CO x = —jruci i l)


44. A teacher w ants to give each student 2 pencils. A store is selling pencils in boxes of 24.
    If the teacher has a total of 125 students, how m any boxes of pencils should h e buy?
    CO 5 CO 6 CO 10 CO 11

Mixed Review

Solve each percent problem. ^ See Lesson 2-9.

45. W hat p ercen t of 12 is 8? 46. W hat is 35% of 185? 47. 20% of w hat n u m b e r is 4.2?

Get Ready! To p r e p a r e f o r Le sso n 3 - 1 , d o Ex e r c i se s 4 8 - 5 1.

Graph the numbers on the same number line. Then order them from least ^ See Lesson 1 -3.

to greatest.

48.-3 49. | 50.2 51.-2.8

7.2 m ~ 7 m

150 Ch ap t er 2 So l v i n g Eq u a t i o n s