I am solving prob 4 on pg 933 in kaplan gmat 2014 book -I have a basic maths qs
Is 2+2^3= 4^3 or you cant simplify this 2+2^3 any further?
Basic maths question
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ashblog02 wrote:I am solving prob 4 on pg 933 in kaplan gmat 2014 book -I have a basic maths qs
Is 2 + 2^3 = 4^3 or you cant simplify this 2+2^3 any further?
To test whether 2 + 2^3 = 4^3, evaluate both sides. We get . . .
2 + 8 = 64
10 = 64 . . . NOPE
We can't really do much to simplify 2 + 2^3, especially since this evaluates to be a small number (10).
Of course, you could factor to get:
2 + 2^3 = 2(1 + 2^2)
= 2(1 + 4)
= 2(5)
= 10
I hope that helps.
Cheers,
Brent
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Hi ashblog02,
One of the basic algebra rules that you were probably taught when you were younger is "combine LIKE terms"; this concept is tested repeatedly on the GMAT, but the rules are consistent, regardless of what the "terms" are.
For example:
2 + 3 = 5 similar terms means you can combine them
2 + x doesn't turn into anything else because the terms are different
y + 3y = 4y
5 cars + 7 cars = 12 cars
(root7) + (root7) = 2(root7)
Sometimes you can change what a term "looks like" and then combine it with another term:
For example:
(root2) + (root50) = (root2) + 5(root2) = 6(root2)
Keep an eye out for ways to combine like terms and simplify expressions; just remember though - they have to be LIKE terms.
GMAT assassins aren't born, they're made,
Rich
One of the basic algebra rules that you were probably taught when you were younger is "combine LIKE terms"; this concept is tested repeatedly on the GMAT, but the rules are consistent, regardless of what the "terms" are.
For example:
2 + 3 = 5 similar terms means you can combine them
2 + x doesn't turn into anything else because the terms are different
y + 3y = 4y
5 cars + 7 cars = 12 cars
(root7) + (root7) = 2(root7)
Sometimes you can change what a term "looks like" and then combine it with another term:
For example:
(root2) + (root50) = (root2) + 5(root2) = 6(root2)
Keep an eye out for ways to combine like terms and simplify expressions; just remember though - they have to be LIKE terms.
GMAT assassins aren't born, they're made,
Rich