In a bakery, 70% of the doughnuts are glazed. If glazed doughnuts acco

Question

In a bakery, 70% of the doughnuts are glazed. If glazed doughnuts account for 21% of all pastries in the bakery, what percent of all pastries in the bakery are doughnuts?

A. 14.7%
B. 24%
C. 28%
D. 30%
E. 35%

0akshay0 · Accepted Answer

Led D be total Doughnuts, G be Glazed Doughnuts, and P be the total pastries. 70% of the doughnuts are glazed => 0.7D = G glazed doughnuts account for 21% of all pastries => G = 0.21P 0.7D = 0.21P => D/P = 0.3 => 30% Hence Option D is correct. Hit Kudos if you liked 8-)

BillyZ · Answer

70% glazed doughnuts = 21% pastries

100% doughnuts = X% pasties

X% pastries =  \frac{(100*21)}{70}  pastries = 30% pasties

Answer = D

SeregaP · Answer

try smart numbers: e.g. total 100 donats, then 70 glazed
70-21
?-100
total number of pastries is 7000/21
100/ (7000/21)=2100/7000=21/70=3/10=30%

praneet87 · Answer

is this a 600-700 question or lesser?

Bunuel · Answer

Check the difficulty level of a question in tags and in original post's stats.

Nunuboy1994 · Answer

Using algebra we can disentangle this problem and translate it into a relatively simple fraction- without actually having to pick numbers or test values- they key to understanding this question is knowing that if 70% of doughnuts comprises 21% of ALL pastries, then 70 percent of the doughnuts divided by .21 will give you the total number of pastries. And of course if we know that 70% of all doughnuts are glazed then we must also know the total number of doughnuts.

Total Doughnuts/ All Pastries = answers

JeffTargetTestPrep · Answer

We can let the total number of pastries = p, the number of donuts = d, and the number of glazed donuts = g. We want to determine d/p x 100%, which is the expression for the percentage of donuts in the bakery. 
 
Let’s create the following equation:
 
0.7d = g
 
g = 0.21p
 
Since both equations equal g, we can equate them. Thus, we have: 
 
0.7d = 0.21p
 
d = 0.21p/0.7
 
d = 0.3p
 
We need to determine (d/p) x 100%:
 
(0.3p/p) x 100% = 0.3 x 100% = 30%
 
Answer: D

generis · Answer

Use smart numbers. The 21% figure is not straightforward. Try 60 or 120. Both integers often work with unusual percentages.

# of doughnuts =  60

# of glazed doughnuts =  42 
70 percent of 60 doughnuts are glazed 
 0.7*60=42  glazed doughnuts

Total # of pastries
42 glazed doughnuts equal 21% of all Pastries, P
 42=.21P 
 P=\frac{42}{.21}=\frac{4,200}{21}=200  Pastries

Doughnuts are what percent of all pastries? 
D = 60, P = 200

Percent:  (\frac{Part}{Whole}*100)=(\frac{D}{P}*100) 
Percent:  (\frac{60}{200}*100)=(\frac{3}{10}*100)=(.30*100)=

30  percent

Answer D

bumpbot · Answer

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In a bakery, 70% of the doughnuts are glazed. If glazed doughnuts acco

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