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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 01:17
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B
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35% (medium)

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73% (01:45) correct 27% (02:14) wrong based on 82 sessions

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If a is less than 80% of b, is a less than 50?

(1) b – a = 20

(2) b < 50
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B
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 01:32
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If a is less than 80% of b, is a less than 50?

(1) b – a = 20
a=10, b=30, a<50
a=50, b=70, a>=50
NOT SUFFICIENT

(2) If b<50, then it must be true that a<50
SUFFICIENT

FINAL ANSWER IS (B)

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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 02:04
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given ; a<.8b
is a<50
#1
b – a = 20
we get b<100 and a<80
so for b = 99 , a=79 ; NO
b=60, a= 40 ; yes
insufficient
#2
b < 50
a value has to be 50*.8 ; <40 ; always yes
IMO B sufficient

If a is less than 80% of b, is a less than 50?

(1) b – a = 20

(2) b < 50
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 02:22
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If a is less than 80% of b, is a less than 50?
Given a < .8b
Find out - a < 50?

(1) b – a = 20
If b = 100, then a = 80, answer is no
if b = 60, then a = 40, answer is yes
Insufficient

A D / B C E

(2) b < 50
We know that a < .8b so, it means a < 50 always.
Sufficient

'B' is the winner
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 05:22
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(1) insufic
a<4/5b; b-a=20, b=20+a
a<4/5(20+a), a<80

(2) sufic
a<4/5b, a<4/5(50)

Ans (B)
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 06:48
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a is less than 80% of b
--> a < 0.8b < 4/5b
--> 5a < 4b ....... (1)

(1) b – a = 20
--> b = a + 20
From (1),
5a < 4(a + 20)
--> 5a < 4a + 80
--> a < 80
a can be between 50 * 80 or less than 50 --> Insufficient

(2) b < 50
Maximum value og b is close to 50 (assume 50)
--> a < 0.8(50) < 40
--> a is DEFINITELY less than 50 --> Sufficient

Option B
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 15:31
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If a is less than 80% of b, is a less than 50?
\(a < (\frac{4}{5})b\)

(Statement1): b – a = 20
--> \(b =20+a\) --> \(a < (\frac{4}{5})(20+a)\)

\(a < 16+ (\frac{4}{5})a\)
\(\frac{a}{5} < 16\) --> \(a < 80\)
--> a could be 30(YES) or 55(NO)
Insufficient

(Statement2): b < 50
Let's say that the maximum value of b is 50
--> \(a < (\frac{4}{5})*50\)
a < 40
Sufficient

The answer is B.
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 21:39
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If a is less than 80% of b, is a less than 50?

(1) b – a = 20

(2) b < 50
Given that, a < 80 % of b
a < 4b/5……..(1)

From statement (1), b – a = 20
or, b = 20 + a, putting in the equation no.(1)
we get, a <4/5*(20 + a)
or, 5a < 80 + 4a
or, a < 80, a could be less than 5 or greater than 50, Not sufficient.

From statement (2), b < 50
or, 20 + a < 50
or, a <40, yes. Sufficient.
Answer:B
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If a is less than 80% of b, is a less than 50? 11 Feb 2020, 22:10
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If a is less than 80% of b, is a less than 50?

a<4b/5

(1) b – a = 20......then a<80.......so a can be >/< 50.

INSUFFICIENT

(2) b < 50......suppose The max value of b is 50....then the max value of a becomes 40..... sufficient to say a is always less than b


OA:B

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If a is less than 80% of b, is a less than 50? 04 Aug 2022, 18:47
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