Fractions, ratios, percentages, exponents, number patterns, word problems without variables, etc.
WB67605
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Joined: Sun Feb 19, 2012 6:04 am
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4[(.5)^4(.6)^3] + 4[(.5)^4(.6)^3(.4)] = 4(.3)^3(.7)

I need some help understanding how to come to this answer. Specifically how to keep the answer in exponential form. Certainly if I convert everything I can come up with an answer without an exponent, but that doesn't help in my case.

stapel_eliz
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4[(.5)^4(.6)^3] + 4[(.5)^4(.6)^3(.4)] = 4(.3)^3(.7)

I need some help understanding how to come to this answer. Specifically how to keep the answer in exponential form.
Just to clarify, are you asking how the left-hand side was converted from two added exponential expressions into the right-hand side's one exponential expression?

Thank you!

little_dragon
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Joined: Mon Dec 08, 2008 5:18 pm
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4[(.5)^4(.6)^3] + 4[(.5)^4(.6)^3(.4)] = 4(.3)^3(.7)
1st factor apart 2 get what they put in the ans:
.6=.3*2
4*.5^4*.6^3=4*.5^4*.3^3*2^3
2nd factor this out:
4*.3^3[.5^4*2^3 + .5^4*2^3*.4]
3rd do inside the brackets:
.5*2=1
.5*1+.5*1*.4
.5+.2=.7