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Smartphones are on sale. A smartphone now costs only 80% of its original price. By how many per cent would we need to increase the current price of the smartphone in order to bring it back to the original price?

Let a be the original price, b - the current price, and x - the answer we are looking for, so we need to increase b by x % in order to get a . So a=b+b x% (the original price a equals the current price b + t...
AP
Answered by Aleksejs P. Maths tutor
3901 Views

In a sale the price of a shirt is reduced by 60%. The sale price is £7.98. What is the original price?

Reduced by 60%=4/5 Original price * 0.4=£7.98 Original price=7.98/0.4=19.95 ∴ Original price= £19.95
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Answered by Riccardo R. Maths tutor
7487 Views

Kelly is trying to work out the two values of w for which 3w-w^3=2. Her values are 1 and -1. Are her values correct?

Sub in her values to see if the LHS and the RHS of the equation equate: w=1: 3(1)-(1)^3=2 >>> 3-1=2 >>> 2=2 ✅ Therefore 1 is a correct value. w=-1: 3(-1)-(-1)^3=2 >>> -3+1=2 >&g...
EB
Answered by Emma B. Maths tutor
5317 Views

At a school number of boys : number of girls = 9 : 7 There are 116 more boys than girls. Work out the total number of students at the school.

B:G --> 9:7 Expressed as fractions of the whole group, boys are 9/16 of the group and girls are 7/16 of the group. We can use algebra to work out the total group number. For our working, I will use x to r...
DM
Answered by Dionne M. Maths tutor
16536 Views

White paint costs £2.80 per litre. Blue paint costs £3.50 per litre. White paint and blue paint are mixed in the ratio 3 : 2. Work out the cost of 18 litres of the mixture.

The ratio given tells us that our paint mixture of 18 litres consists of 3 + 2 = 5 parts . Each part therefore consists of 18/5 = 3.6 litres of paint . If we need 3 parts white paint, thats: 3 (parts) x 2.80...
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Answered by Vicente O. Maths tutor
4173 Views