if x is equal to the sum of the even integers from 40 to 60, inclusive and y is the number of even integers from 40 to 60, inclusive what is the value of x + y?
1. 550
2. 551
3. 560
4. 561
5. 571
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what is the effective way of solving this?
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g.shankaran
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no of even integer between 40 to 60 is> 60-40/2+1 = 11 =yg.shankaran wrote:if x is equal to the sum of the even integers from 40 to 60, inclusive and y is the number of even integers from 40 to 60, inclusive what is the value of x + y?
1. 550
2. 551
3. 560
4. 561
5. 571
sum of even integer from 40 to 60 is> 11/2(40+60) = 550 =x
Now x+y= 550+11= 561
ans is 4
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GMATGuruNY
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To determine the sum of evenly spaced integers, use the following formula:g.shankaran wrote:if x is equal to the sum of the even integers from 40 to 60, inclusive and y is the number of even integers from 40 to 60, inclusive what is the value of x + y?
1. 550
2. 551
3. 560
4. 561
5. 571
Sum = (number of integers) * (average of biggest and smallest)
To count the number of evenly spaced integers in a set:
Number of integers = (Biggest - Smallest)/(distance between each successive pair) + 1
With even integers, the distance between each successive pair is 2.
Thus, given the even integers from 40 to 60, inclusive:
Number of integers = (60-40)/2 + 1 = 11.
Average of biggest and smallest = (60+40)/2 = 50.
Sum = number * average = 11*50 = 550.
Sum + number = 550+11 = 561.
The correct answer is D.
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vinayreguri
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Raw Solution:
x=(40+42+44+46+48)+(50+52+54+56+58)+60
y=(60-40)/2(inclusive of 40 & 60)=22/2=11
Now x+y=550+11=561
Ofcourse, This is time consuming.
x=(40+42+44+46+48)+(50+52+54+56+58)+60
y=(60-40)/2(inclusive of 40 & 60)=22/2=11
Now x+y=550+11=561
Ofcourse, This is time consuming.
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cans
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x=40+42+....+60
y=11
x=(11/2)(100)=550
x+y=561
y=11
x=(11/2)(100)=550
x+y=561
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Cans!!
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Cans!!
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Tega1984
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o.k here's my solution. factor out 2 to be left with 2(20+21+22+23...all the way to 30) and divide by 2. 2's will cancel and you're left with 20+21+22.... Now multiply 30 by 31 to get 930. than you should multiply 19 by 20 to get 380 and subtract 380 from 930 to get 550. This 550 is the sum of all even integers from 40 to 60. Than just count the number of even integers from 40 to 60(it's 11) and sum those two numbers. 550+11=561 So the answer is 4.
g.shankaran wrote:if x is equal to the sum of the even integers from 40 to 60, inclusive and y is the number of even integers from 40 to 60, inclusive what is the value of x + y?
1. 550
2. 551
3. 560
4. 561
5. 571
