A table tennis club increased its membership by exactly 20% in the calendar year.
Select all of the following which could be the number of members the table tennis club had at the end of 2018.
24  35  40  52  66 





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A table tennis club increased its membership by exactly 20% in the calendar year.
Select all of the following which could be the number of members the table tennis club had at the end of 2018.
24  35  40  52  66 





`24 and 66`
`text(Membership increase) = 1/5`
`=> 6/5 xx text(old membership = whole number)`
`=>\ text{Old membership (start of 2018) must finish in 5 or 0.}`
`text(Possible changes):`
`5 > 6`  `10 > 12` 
`15 > 18`  `20 > 24` 
`25 > 30`  `30 > 36` 
`35 > 42`  `40 > 48` 
`45 > 54`  `55 > 66` 
`:. 24, 66`
At the start of a week, Miley had 2.59 GB of storage on her mobile phone.
During the week she downloaded 60 songs which each took up 6.5 MB of storage.
Miley also downloaded a TV show.
At the end of the week, she had 850 MB of storage left.
How many gigabytes of storage did the TV show use?
Give your answer as a decimal, to two decimal places.
GB 
`text(1.35 GB)`
`text(Original storage = 2590 MB)`
`text(Songs)`  `= 60 xx 6.5` 
`= 390\ text(MB)` 
`:.\ text(TV show size)`
`= 2590  (390 + 850)`
`= 1350\ text(MB)`
`= 1.35\ text(GB)`
In a racing car season, the top three finishers in each race are awarded points.
Vangio was awarded a total of 25 points.
What is the greatest number of races in which Vangio could have been in the top three?
5  6  7  8 




`6`
`text(The greatest number of top 3 finishes occur with)`
`text(the following points results:)`
`8 + 5 + 3 + 3 + 3 + 3 = 25`
`:. 6\ text(events is the highest.)`
Maria has 500 avocados to pack into boxes.
Each box has room for 3 layers of avocados with 27 avocados in each layer.
Maria packs as many full boxes as possible.
How many avocados are left over?
7  12  14  17 




`14`
`text(One solution:)`
`text(Avocados in 1 box)`  `= 3 xx 27` 
`= 81` 
`text(Full boxes)`  `= 500 ÷ 81` 
`= 6.17…`  
`= 6\ text(full boxes)` 
`:.\ text(Leftover)`  `= 500  (6 xx 81)` 
`= 500  486`  
`= 14` 
Write 1001 as the product of its prime factors.
`7 xx 11 xx 13 = 1001`
`text(By trial and error, divide 1001 by prime numbers)`
`text(until the result is a whole number.)`
`1001 ÷ 7`  `= 143` 
`143 ÷ 11`  `= 13` 
`:. 7 xx 11 xx 13 = 1001`
A number is multiplied by itself and then 12 is added.
The answer is 28.
What is the number?
`4`
`text(Reversing the order of operations:)`
`2812=16`
`sqrt16 = 4`
`text(Check answer:)`
`4 xx 4 +12=28`
`:.\ text(The number is 4.)`
An insect expert estimates that an anthill 30 cm high contains `10^8` ants.
He also estimates that a 25 cm high anthill contains `10^7` ants.
If his estimations are correct, how many more ants live in the 30 cm high anthill than the 25 cm high one?
`text(9 million)`  `text(10 million)`  `text(90 million)`  `text(100 million)` 




`text(90 million)`
`text(The extra ants in the 30 cm high anthill)`
`= 100\ 000\ 000  10\ 000\ 000`
`=90\ 000\ 000`
`=90\ text(million)`
Kim bought these 5 items.
The total mass of Kim's items is closest to
`3\ text(kg)`  `4\ text(kg)`  `5\ text(kg)`  `8\ text(kg)` 




`text(5 kg)`
`text(2 kg + 1.5 kg + 300 g + 350 g + 400 g)`
`=2\ text(kg + 1.5 kg + 0.3 kg + 0.35 kg +0.4 kg)`
`=4.55\ text(kg)`
`=5\ text{kg (nearest kg)}`
Zilda has 4 children.
Each child needs 6 pens when they start school for the new year.
Zilda has no pens when she goes to the shop.
The shop sells its pens in packets of 5.
How many packets does Zilda need to buy?
`2`  `4`  `5`  `6` 




`5\ text(packets)`
`text(Pens required)`  `= 4 xx 6` 
`= 24` 
`:.\ text(Packets required)`  `= 24/5` 
`= 4.8`  
`= 5` 
The product of three different whole numbers is 40.
What is the largest possible sum of the three numbers?
`23`
`40 = 20 xx 2 xx 1`
`20 + 2 + 1 = 23`
Murray picks a 2 digit number at random.
He can give the following clues about his number:
What is Murray's number?
`64`
`8^2 + 6^2`  `= 100` 
`64 + 36`  `= 100` 
`=>\ text(64 is not divisible by 9.)`
An orchard has the following trees:
How many trees are growing in the orchard?
`95\ text(trees)`
`text(5 lemon trees)`
`text(15 pear trees)`
`text(12 apple trees)`
`text(2 nectarine)`
`text(1 plum)`
`text(60 avocado trees)`
`:.\ text(Total trees) = 95`
A butcher sells sausages in bags of four.
For a party, 20 sausages are needed.
How many bags of sausages are needed?
`4`  `5`  `25`  `80` 




`5`
`text(Bags needed) = 20/4 = 5`
Olaf's receipt from a Battery World store was torn and part of it was thrown in the rubbish.
He knew:
His credit card statement showed that he spent `$83.90` at the Battery World store.
About how much did the hard drive cost?
`$5`  `$17`  `$28`  `$67` 




`$17`
`text(C) text(ost of batteries and USB sticks)`
`~~ (3 xx 9) + (5 xx 8)`
`~~ $67\ \ text{(just under)}`
`:.\ text(Hard Drive cost)`  `~~ 83.90  67` 
`~~ $16.9`  
`~~$17` 