ulangle ABCD is (16x + 12y) cm.
* 45 each
ite an
EXERCISE 110
ITY
Statement
Variable
ch of her
birthday
a over, find a
ates she had
nds who
Statement
using expression
ed home in
B got off at
B, and c
half her son's age
A's and
the
Sonia's age is 5 years less than
twice Purnima's age
The speed of a bus is 50 km/hour
more than half the speed of the car
The cost of a pen is increased by
3. Sheila bought 5 pens. How
much did she pay?
times
te
otal
Perimeter of a rectangle whose
length is 5 cm more than its breadth.
iu
Cost of one book is 7 more than
three times the cost of a pen.
1
My walking speed is km/hour
less than twice that of my daughter.
ALGEBRA I 237
Complete the following table by using a variable and forming a corresponding expression
Sanya ate 3 more biscuits than Vikram.
Aarya has 7 stamps less than Aditya
Sarla is twice as old as Satwinder
Anjali's age is 28 years more than
Air each of the given statements.
Answers
Answer:
Let’s search the problem for clues as to what it will be testing, as this will help shift our minds to think about what type of math knowledge we’ll use to solve this question. Pay attention to any words that sound math-specific and anything special about what the numbers look like, and mark them on our paper.
The question mentions the average of a set of numbers, which is part of the Numerical Methods for Describing Numbers GRE math skill. Let’s keep what we’ve learned about this skill at the tip of our minds as we approach this question.
What Do We Know?
Let’s carefully read through the question and make a list of the things that we know.
We want to find the least possible value of a
a≤b≤c≤d≤e≤110
We know that the average of a,b,c,d,ande is 100
Develop a Plan
The question asks about averages, so let’s start by recalling our equation for calculating the average of a group of numbers.
Average=
SumofValues
NumberofValues
So for example, if the sum of 10 numbers is 200, then the average of those 10 numbers is
200
10
, or 20. Viewed a slightly different way, if the average of 10 numbers is 20, then the sum of those 10 numbers is 200. We should keep our minds flexible when it comes to sums and averages. Some questions it’ll be easier to work with sums, whereas for other questions it’ll be easier to work with averages.