Question

7 jack increased his donations by 11%. this is equal to multiplying that amount by:
a 11%
b 110%
c 1.11
d 1.1

8 jill multiplied her donations by 0.86. this is equal to a percentage change of a:
a 24% decrease
b 14% decrease
c 14% increase
d 24% increase

9 what is the percentage increase if the original price is $50 & the new price is $60?
a $10
b 10%
c 20%
d $20

10 jenny has 1250 photos stored on her mobile. she wants to print 20% of these. if her photos cost 9 cents a photo to print, how much will this printing cost?
a $2250
b $22.50
c $250
d $112.50

Explanation:

Solve Question 7

Find the multiplier for an \(11\%\) increase.
An increase of \(11\%\) means:

$$ 100\% + 11\% = 111\% $$

Convert this percentage to a decimal:

$$ \frac{111}{100} = 1.11 $$

This matches option C.

Solve Question 8

Find the percentage change for a multiplier of \(0.86\).
A multiplier less than \(1\) represents a decrease:

$$ 1 - 0.86 = 0.14 $$

Convert the decimal difference to a percentage:

$$ 0.14 \times 100\% = 14\% \text{ decrease} $$

This matches option B.

Solve Question 9

Calculate the percentage increase from \(\$50\) to \(\$60\).
Find the absolute increase:

$$ 60 - 50 = 10 $$

Calculate the percentage relative to the original price:

$$ \frac{10}{50} \times 100\% = 20\% $$

This matches option C.

Solve Question 10

Calculate the total printing cost.
First, find \(20\%\) of the \(1250\) photos:

$$ 1250 \times 0.20 = 250 \text{ photos} $$

Multiply the number of photos by the cost per photo (\(9\) cents or \(\$0.09\)):

$$ 250 \times 0.09 = 22.50 $$

The total cost is \(\$22.50\). This matches option B.

Answer:

Question 7

• A 11%
• B 110%
• C 1.11 (Correct answer)
• D 1.1

Question 8

• A 24% decrease
• B 14% decrease (Correct answer)
• C 14% increase
• D 24% increase

Question 9

• A $10
• B 10%
• C 20% (Correct answer)
• D $20

Question 10

• A $2250
• B $22.50 (Correct answer)
• C $250
• D $112.50