Zhuhai Library Recruitment Written Test Content

( 1)∵30- 15= 15,4÷ 15=4 15,

∴ The time for Xiao Cong to consult materials in the library and the speed for Xiao Cong to return to school are15min and 415km/min respectively.

So the answer is 15,415;

(2) As can be seen from the figure, S is a proportional function of T 。

Let the analytical expression of the function be s=kt(k≠0 and constant).

Substitution into point (45, 4) results in

4=45k，

The solution is k = 445.

The functional relationship between s and t is s = 445t (0 ≤ t ≤ 45).