Question

Please answer my mock rev question !!

Answer 1

(a) 8800000

(b) Barcelona had the least population in 2018

(c) The difference in population is 2.9 x
`10^(7)`

Explanation:

(a) Since '10' is raised to a positive power, the decimal will be moving in the forward direction, In other words, it will move towards the right. Therefore, the decimal will be moving 6 places forward. After which, the empty slot(s) will be occupied by zeros

8.8 x
`10^(6)` = 8800000

(b) First notice that three out of the five cities have population expressed in
`10^(6)` (where 6 is the least power). Then notice that out of those three cities, the smallest number corresponds to Barcelona (i.e. 5.5).

Therefore, Barcelona had the least population in 2018

(c) Population of:

Tokyo: 3.7 x
`10^(7)`

Ahmedabad: 7.7 x
`10^(6)`

First, make sure the two numbers are expressed in the same standard form (meaning 10 is raised to the same power in both cases):

Tokyo: 3.7 x
`10^(7)` = 3.7 x 10 x
`10^(6)` =37 x
`10^(6)`

Ahmedabad: 7.7 x
`10^(6)`

Next step:

37 x
`10^(6)` - 7.7 x
`10^(6)`

= (37 - 7.7) x
`10^(6)`

= 29.3 x
`10^(6)`

= 29 x
`10^(6)` (Corrected to 3 significant figures)

= 2.9 x 10 x
`10^(6)`

= 2.9 x
`10^(7)`