What is \(4.2681\) when rounded to \(3\) decimal places?
- \(4.26\)
- \(4.27\)
- \(4.268\)
- \(4.269\)
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What is \(4.2681\) when rounded to \(3\) decimal places?
\(C\)
\(4.2681 \approx\ 4.268 \ (3\ \text{d.p.})\)
\(\Rightarrow C\)
Peter rides his bike at a speed of 27 km/h.
What is this speed in m/s?
(A) `7.5`
(B) `18.75`
(C) `97.2`
(D) `450`
`A`
`text(27 km/h)` | `= 27\ 000\ text(metres per hour)` |
`= (27\ 000)/60\ text(metres per minute)` | |
`= (27\ 000)/(60 xx 60)\ text(metres per second)` | |
`=7.5\ text(m/s)` |
`=> A`
During a ten-minute period, Kath is exercising and Jim is resting.
How much more air would Kath breathe than Jim during this time?
(A) 40 Litres
(B) 94 Litres
(C) 940 Litres
(D) 1060 Litres
`C`
`text(Kath’s air volume)`
`= 10 xx 100`
`=1000\ text(L)`
`text(Jim’s air volume)`
`= 10 xx 6`
`= 60\text(L)`
`:.\ text(Extra air that Kath breathes)`
`= 1000 – 60`
`= 940\ text(L)`
`=> C`
A measurement of 72 cm is increased by 20% and then the result is decreased by 20%.
What is the new measurement, correct to the nearest centimetre?
(A) 46 cm
(B) 69 cm
(C) 72 cm
(D) 104 cm
`B`
`text(72 increased by 20%)`
`= 72 + (text(20%) xx 72) = 86.4\ text(cm)`
`text(86.4 decreased by 20%)`
`= 86.4\ – (text(20%) xx 86.4) = 69.12\ text(cm)`
`=> B`
How many square centimetres are in 0.0075 square metres?
(A) 0.75
(B) 7.5
(C) 75
(D) 7500
`C`
`text(S)text(ince 1 m²)` | `= 100\ text(cm) xx 100\ text(cm)` |
`= 10\ 000\ text(cm²)` |
`:.0.0075\ text(m²)` | `= 0.0075 xx 10\ 000` |
`= 75\ text(cm²)` |
`=> C`
Bhawana purchases pool chlorine in a new container which holds 35 kg.
She begins using this new container on the first day of a week.
How many full weeks should this container last? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`text(15 full weeks.)`
`text(Cups used per week)` | `= 3 + 6 = 9` |
`text(Chlorine usage per week)` | `= 9 xx 250text(g)` |
`= 2250 text(g)` |
`text(Total chlorine available)\ = 35text(kg) = 35\ 000\ text(grams)`
`text(Time it will last)` | `= (35\ 000)/2250` |
`= 15.555…` |
`:.\ text(The container will last 15 full weeks.)`