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I'm having problem figuring this question out: Assume the brain is 70% water. If the average adult human brain weighs 1.4 kg, how many kilograms of water does it contain? Thank you for any help.
Your answer is 980 grams of water or .98 kilograms of water.
How did I find the answer? I took the weight of the brain and converted it into grams which is 1400 grams. Then I multiplied that by .7 and I got 980. Then I converted that value into kilograms which ended up being .98
1.4 x 0.7 = 0.98 kg
to figure this out
100% of the brain = 1.4 70% of the brain = x
cross multiply
100% of the brain multiplied by x = 1.4 x 70% of the brain
100% = 100/100 = 1 70% = 70/100 = 0.7
1x = 1.4 x 0.7 x = 0.98
density of water is 1g/m^3
so, 75/100*1.4kg x 1m^3/gram * 1000gram /kg = 980 grams. (use conversion factors, they are really the easiest)
Thanks for the correction, wasn't thinking to well since I did something entirely different to find the answer lol.
To figure it out simply multiply 1.4 by .7 and you will get the percentage made up by water.
.98 but I'm sure you figured that out already :P
yep but shouldnt the 70 be multiplied?
