Question

3. Express each of the following in km/h.
(a) 8.4 km/min (b) 315 m/s
(c) 242 m/min (d) 125 cm/s​

Answer 1

Answer :

a.) 8.4 km/min

$\\ \sf \: \frac{8.4 \: km}{1 \: min} \\ \\ \\ \implies \sf \: \frac{8.4 \: km}{ \bigg( \dfrac{1}{60} h\bigg)} \\ \\ \\ \implies \sf \: (8.4 \times 60) \: km /h \\ \\ \\ \implies \sf \: 504 \: km /h \\ \\ \\ \large{ \underline{ \boxed{ \sf{ \orange{504 \: km /h}}}}}$

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b.) 315 m/s

$\\ \\ \sf \: 315 \: m /s \\ \\ \\ \implies \sf \bigg(315 \times \dfrac{18}{5} \bigg) \\ \\ \\ \implies \sf \: 1134 \: km /h \\ \\ \\ \large{ \underline{ \boxed{ \sf{ \blue{1134 \: km /h}}}}}$

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c.) 242 m/min

$\\ \\ \sf \: 242 \: m /min \\ \\ \\ \implies \sf \: \dfrac{242 \: m}{1 \: min} \\ \\ \\ \implies \sf \: \frac{ \bigg(\dfrac {242}{1000} \bigg) km}{ \bigg( \dfrac{1}{60} \bigg) \: h } \\ \\ \\ \implies \sf \bigg( \dfrac{242}{1000} \times 60 \bigg) \: km /h \\ \\ \\ \implies \sf \: 14.52 \: km /h \\ \\ \\ \large{ \underline{ \boxed{ \sf{ \green{14.25 \: km /h}}}}}$

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d.) 125 cm/s

$\\ \\ \sf \: 125 \: cm /s \\ \\ \\ \implies \sf \: \dfrac{125 \: cm}{1 \: sec} \\ \\ \\ \implies \sf \: \frac{ \bigg( \dfrac{125}{1000 \times 100} \bigg)km}{ \bigg( \dfrac{1}{3600} \bigg)h} \\ \\ \\ \implies \sf \: 4.5 \: km /h \\ \\ \\ \large{ \underline{ \boxed{ \sf{ \red{4.5 \: km /h}}}}}$

Answer 2

Answer:

315m/

Step-by-step explanation: