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Percentages Homework Grid: Math Practice & Problem Solving

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Percentages Homework Grid
Your aim is to score at least 50 points by choosing different tasks. You must pick one from each row: fluency, reasoning and problem-solving.
Bronze
Silver
Gold
Fluency
(5 points)
Calculate 23% of £160.
Reduce £90 by 23%.
The price of a coat is reduced by 23% in the
sale. It now costs £92.40. What did it cost
before the sale?
Reasoning
(10 points)
Which of these gives the larger amount: Explain why the answer to each of these Statistics tell us that female employees in the
17% of £50 or 50% of £17?
must be the same: 47% of 9 and 9% of 47. UK earn 9.1% per hour less than their male
colleagues. If all female employees were to
receive a 10% increase on their pay, would
this now mean they were earning more, less
or the same as the male employees?
ProblemSolving
(15 points)
Beth visits a large department store during
the January sales. She spots these two
sale stickers. Which one has the larger
percentage reduction?
Was £39.99
Now £25!
The Big
One!
(30 points)
Normal price £52
Take 35% off!
Ellie and Frederic are selling sweets at their
respective schools’ tuck shops. Ellie buys
100 sweets for £28 and sells them for £45.
Frederic buys 50 sweet for £13 and makes
a £7.50 profit. Who makes the bigger
percentage profit?
I invest some money in a savings account.
During the first year, I received 2% interest
back, then in the second year I receive
3%. What percentage interest have I
received overall?
By looking online at “payday loan” lenders, design a short presentation to explain to your classmates why borrowing from one of these
is never a good idea.
visit twinkl.com
Percentages Homework Grid Answers
Your aim is to score at least 50 points by choosing different tasks. You must pick one from each row: fluency, reasoning and problem-solving.
Fluency
(5 points)
Reasoning
(10 points)
Bronze
Silver
Gold
Calculate 23% of £160.
Reduce £90 by 23%.
10% is £16 so 20% is £32
1% is £1.60 so 3% is £4.80
In total, 23% is £36.80
23% is £20.70
90 – 20.70 = £69.30
The price of a coat is reduced by 23% in the sale. It
now costs £92.40. What did it cost before the sale?
Which of these gives the larger amount: 17% of £50
or 50% of £17?
Explain why the answer to each of these must be the
same: 47% of 9 and 9% of 47.
These actually give the same answer: £8.50.
We can calculate these using the decimal
equivalents:
0.47 × 9
0.09 × 47
To work out why, we can look at the decimal
equivalents: 50 × 0.17 or 17 × 0.5. If we were to
calculate these by hand, we would work out the
answer to the integer problems then divide by 100.
ProblemSolving
(15 points)
Beth visits a large department store during the
January sales. She spots these two sale stickers.
Which one has the larger percentage reduction?
Was £39.99
Now £25!
Normal price £52
Take 35% off!
The first deal has a percentage reduction of
14.99
39.99 × 100 = 37.5%. Therefore, the first deal has a
larger percentage reduction.
The Big One!
(30 points)
A 23% reduction is 77%
92.40 ÷ 0.77 = £120
To calculate the answer in both cases, we would
work out 47 × 9 and then divide by 100. Hence
they will give the same answer.
Ellie and Frederic are selling sweets at their
respective schools’ tuck shops. Ellie buys 100 sweets
for £28 and sells them for £45. Frederic buys 50
sweet for £13 and makes a £7.50 profit. Who makes
the bigger percentage profit?
Ellie’s percentage profit is
17
×
28
Frederic’s percentage profit is
100 = 60.7%
7.50
13
Statistics tell us that female employees in the UK earn
9.1% per hour less than their male colleagues. If all
female employees were to receive a 10% increase on
their pay, would this now mean they were earning
more, less or the same as the male employees?
Currently, female employees are earning 90.9% of
what male employees earn.
A 10% increase would be calculated by 90.9 × 1.1
= 99.99%. This would mean they were still earning
slightly less than their male colleagues.
I invest some money in a savings account.
During the first year, I received 2% interest
back, then in the second year I receive
3%. What percentage interest have I received overall?
1.02 × 1.03 = 1.0506
This is 5.06% interest.
× 100 = 57.7%
Therefore, Ellie makes the bigger percentage profit.
By looking online at “payday loan” lenders, design a short presentation to explain to your classmates why borrowing from one of these is never a good idea.
Responses will vary, but pupils should make reference to inflated interest fees that quickly double the amount that must be paid back.
visit twinkl.com
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