Paint needs to be thinned to a ratio of 2 parts paint to 1.5 parts wat

Question

Paint needs to be thinned to a ratio of 2 parts paint to 1.5 parts water. The painter has by mistake added water so that he has 6 litres of paint which is half water and half paint. What must he add to make the proportions of the mixture correct?

A. 1 litre paint
B. 1 litre water
C. ½ litre water and one litre paint
D. ½ litre paint and one litre water
E. ½ litre paint

A. 1 litre paint 
B. 1 litre water 
C. ½ litre water and one litre paint 
D. ½ litre paint and one litre water 
E. ½ litre paint

chetan2u · Accepted Answer

Hi,

two ways-
 1) based on choice- 
water and paint are in ratio 1:1.. we have to make it 2:1.5 or 4:3..
so clearly paint has to be added to bring up the ratio of paint..
ONLY A and E are left

Quantity P:W is 3:3 it has to be converted to 4:3..
so clearly 1 liter of P is to be added
ans A

2) Proper method- 
existing ratio = 3:3..
add y to convert to 4:3..
so  \frac{3+y}{3}= \frac{4}{3} ....
 9+3y=12.................3y=12-9...................y=1 
ans A

ronny123 · Answer

Paint needs to be thinned to a ratio of 2 parts paint to 1.5 parts water. The painter has by mistake added water so that he has 6 litres of paint which is half water and half paint. What must he add to make the proportions of the mixture correct?

A. 1 litre paint
B. 1 litre water
C. ½ litre water and one litre paint
D. ½ litre paint and one litre water
E. ½ litre paint

A. 1 litre paint 
B. 1 litre water 
C. ½ litre water and one litre paint 
D. ½ litre paint and one litre water 
E. ½ litre paint

Reqd. ratio = 2 : 1.5 i.e. 4 : 3 between paint and water respectively.
6 litres of paint which is half water(3 litres) and half paint (3 litres)

Right now the ratio is 1:1 
Looking at the options,
A. Paint : Water = 4 : 3 which is the reqd. ratio . Correct Answer
B. Paint : Water = 3 : 4
C. Paint : Water = 4 : 3.5
D. Paint : Water = 3.5 : 4
E. Paint : Water = 3.5 : 3

Answer : A

amanvermagmat · Answer

Required ratio = Paint/Water = 2/1.5 = 4/3
Right now, paint = 3 litres and water = 3 litres

lets say 'x' litres of paint need to be added to make the desired ratio. Then we have:
(3+x)/3 = 4/3 Or 3+x = 4 or x = 1

Hence  A answer

gracie · Answer

let p=litres of paint to be added
3+p=4/7*(6+p)
p=1 litre paint
A

JeffTargetTestPrep · Answer

We are given that the painter needs a ratio of paint to water of 2x : 1.5x.
 
However, he actually has 3 litres of paint and 3 litres of water, which make a ratio of 1 : 1. To make the correct ratio of paint to water, he must add more paint. 
 
We can let n = the number of litres of paint he must add.
 
(3 + n)/3 = 2x/1.5x
 
(3 + n)/3 = 2/1.5
 
1.5(3 + n) = 6
 
4.5 + 1.5n = 6
 
1.5n = 1.5
 
n = 1
 
Thus, he needs to add 1 litre of paint.
 
Answer: A

stne · Answer

Hi Bunuel ,

Instead of using part to part , I am using part to whole , approach, why am I not getting the answer !

\frac{paint }{ Total \hspace{1mm}quantity} = \frac{2}{3.5}  -> Required ratio
Finally after adding x liters of paint to 3 liters of paint already present the ratio of paint to total mixture is  \frac{3+x}{6}

Hence equating the proportions  \frac{2}{3.5}=\frac{3+x}{6}

x =  \frac{3}{7}

Whys is x not coming to 1?

KarishmaB · Answer

Because once you add x litres of paint to the mix, the total mix becomes 6 + x litres.
Hence,

\frac{2}{3.5}=\frac{3+x}{6+x}  
x = 1

stne · Answer

Thank you Karishma.

Sreyoshi007 · Answer

Paint and water need to be in the ratio 2 : 1.5 which is nothing but  4 : 3 .
Now 6 L solution has  equal amounts  of paint and water ( 3 L and 3 L) and we need to bring it to the ratio 4 : 3 (P : W).
Currently W is already 3 L, so if we  add another 1 L of paint  to the 6 L solution, the new ratio will become 4 : 3 as we require.

Hence Answer is A - 1 L of paint.

bumpbot · Answer

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Paint needs to be thinned to a ratio of 2 parts paint to 1.5 parts wat

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