2^5+2^5 + 3^5+3^5+3^5
options:
5^6
13^5
2^6+3^6
2^7+3^8
4^5+9^5
how to solve this without breaking it up ?
my exam is tomorrow.....please can someone help !!
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my exam is tomrrow - please help with this stupid simple eqn
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sudhir3127
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take 2^5 comon and 3^5 comon
2^5(2)+ 3^5(3)
hence 2^6+3^6
hope its clear..
All the very best for ur exam...
2^5(2)+ 3^5(3)
hence 2^6+3^6
hope its clear..
All the very best for ur exam...
The solution provided seems simple...but can someone explain the math?
Are the exponents being multiplied or is there more factoring not shown in the solution.
2(2^5) + 3(3^5)
I see that 2^5 = 32, so 2(2^5) = 64, which is 2^6.
I would have picked the correct answer because the others do not have the same first term on a real GMAT but what about factoring or doing the math of 3^5 or something similar w/o a calculator.
Are the exponents being multiplied or is there more factoring not shown in the solution.
2(2^5) + 3(3^5)
I see that 2^5 = 32, so 2(2^5) = 64, which is 2^6.
I would have picked the correct answer because the others do not have the same first term on a real GMAT but what about factoring or doing the math of 3^5 or something similar w/o a calculator.
Don't overthink the problem. No need to multiply out.
Once you recognize that 2^5+2^5+3^5+3^5+3^ = 2(2^5)+3(3^5) you need to just take the next step and realize that you now have:
2^1(2^5) + 3^1(3^5) and add the exponents to arrive at:
2^6+3^6
Once you recognize that 2^5+2^5+3^5+3^5+3^ = 2(2^5)+3(3^5) you need to just take the next step and realize that you now have:
2^1(2^5) + 3^1(3^5) and add the exponents to arrive at:
2^6+3^6
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Ian Stewart
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There are (at least) two ways to see why the answer is correct. We can factor:evansbd wrote:The solution provided seems simple...but can someone explain the math?
Are the exponents being multiplied or is there more factoring not shown in the solution.
2(2^5) + 3(3^5)
I see that 2^5 = 32, so 2(2^5) = 64, which is 2^6.
I would have picked the correct answer because the others do not have the same first term on a real GMAT but what about factoring or doing the math of 3^5 or something similar w/o a calculator.
2^5 + 2^5 + 3^5 + 3^5 + 3^5 = 2^5(1+1) + 3^5(1+1+1) = 2*2^5 + 3*3^5 = 2^6 + 3^6
Or we can understand that when we add something to itself, this is exactly what it means to multiply something by 2: x+x = 2x. Thus 2^5 + 2^5 = 2*2^5 = 2^6. And if you add something to itself three times, that's the same as multiplying by 3: x+x+x = 3x, so 3^5 + 3^5 + 3^5 = 3*3^5 = 3^6.
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com
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