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Numbers - Common Sense

For COMPETITION
Number of Total Problems: 9.
FOR PRINT ::: (Book)

Problem Num : 1
From : NCTM
Type: Understanding
Section:Numbers 
Theme:None
Adjustment# :
Difficulty: 1

Category Common Sense
Analysis

Solution/Answer


Problem Num : 2
From : NCTM
Type: None
Section:Numbers 
Theme:Case Devision
Adjustment# :
Difficulty: 1

Category Common Sense
Analysis

Solution/Answer


Problem Num : 3
From : NCTM
Type: None
Section:Numbers 
Theme:None
Adjustment# :
Difficulty: 1

Category Common Sense
Analysis

Solution/Answer


Problem Num : 4
From : NCTM
Type: None
Section:Numbers 
Theme:None
Adjustment# :
Difficulty: 1

Category Common Sense
Analysis

Solution/Answer


Problem Num : 5
From : NCTM
Type: Complex
Section:Numbers 
Theme:Num of Equations
Adjustment# :
Difficulty: 2

Category Common Sense
Analysis

Solution/Answer


Problem Num : 6
From : NCTM
Type: Application
Section:Numbers 
Theme:Case Devision
Adjustment# :
Difficulty: 1

Category Common Sense
Analysis

Solution/Answer


Problem Num : 7
From : AMC10
Type:
Section:Numbers 
Theme:
Adjustment# : 0
Difficulty: 1
'

Members of the Rockham Soccer League buy socks and T-shirts. Socks cost $4 per pair and each T-shirt costs $5 more than a pair of socks. Each member needs one pair of socks and a shirt for home games and another pair of socks and a shirt for away games. If the total cost is $2366, how many members are in the League?

mathrm{(A)  } 77qquad mathrm{(B)  } 91qquad mathrm{(C)  } 143qquad mathrm{(D)  } 182qquad mathrm{(E)  } 286

'
Category Common Sense
Analysis

Solution/Answer

Since T-shirts cost 5 dollars more than a pair of socks, T-shirts cost 5+4=9 dollars.

Since each member needs 2 pairs of socks and 2 T-shirts, the total cost for 1 member is 2(4+9)=26 dollars.

Since 2366 dollars was the cost for the club, and 26 was the cost per member, the number of members in the League is 2366div 26=oxed{mathrm{(B)} 91}.

Answer:



Problem Num : 8
From : AMC10
Type:
Section:Numbers 
Theme:
Adjustment# : 0
Difficulty: 1
'

You and five friends need to raise 1500 dollars in donations for a charity, dividing the fundraising equally. How many dollars will each of you need to raise?

mathrm{(A)  } 250qquad mathrm{(B)  } 300 qquad mathrm{(C)  } 1500 qquad mathrm{(D)  } 7500 qquad mathrm{(E)  } ...

'
Category Common Sense
Analysis

Solution/Answer

There are 6 people to split the 1500 dollars among, so each person must raise frac{1500}6=250 dollars. Rightarrowmathrm{(A)}

Answer:



Problem Num : 9
From : AMC10B
Type:
Section:Numbers 
Theme:
Adjustment# : 0
Difficulty: 1
'

As shown below, convex pentagon ABCDE has sides AB=3, BC=4, CD=6, DE=3, and EA=7. The pentagon is originally positioned in the plane with vertex A at the origin and vertex B on the positive x-axis. The pentagon is then rolled clockwise to the right along the x-axis. Which side will touch the point x=2009 on the x-axis?

unitsize(3mm);defaultpen(linewidth(.8pt)+fontsize(8pt));dotfactor=4;pair A=(0,0), Ep=7*dir(105), B=3*dir(0);pair D=Ep+B;pair ...

	ext{(A) } overline{AB}qquad	ext{(B) } overline{BC}qquad	ext{(C) } overline{CD}qquad	ext{(D) } overline{DE}qquad...

'
Category Common Sense
Analysis

Solution/Answer

The perimeter of the polygon is 3+4+6+3+7 = 23. Hence as we roll the polygon to the right, every 23 units the side overline{AB} will be the bottom side.

We have 2009 = 23 	imes 87 + 8. Thus at some point in time we will get the situation when A=(2001,0) and overline{AB} is the bottom side. Obviously, at this moment B=(2004,0).

After that, the polygon rotates around B until point C hits the x axis at (2008,0).

And finally, the polygon rotates around C until point D hits the x axis at (2014,0). At this point the side oxed{overline{CD}} touches the point (2009,0). So the answer is oxed{C}

Answer:



Array ( [0] => 3688 [1] => 3691 [2] => 3694 [3] => 3699 [4] => 3707 [5] => 3716 [6] => 7769 [7] => 7788 [8] => 8115 ) 9