a) 

$46,78\approx 47$

$60,76\approx 61$

$230,26\approx 230$

$3,087\approx 3$

$88,718\approx 89$

b) 

$8,37\approx 8,4$

$17,056\approx 17,1$

$5,89\approx 5,9$

$2,049\approx 2,0$

$35,836\approx 35,8$

c)

$34,0365\approx 34,037$

$8,9677\approx 8,968$

$6,9999\approx 7,000$

$25,1414\approx 25,141$

$48,5858\approx 48,586$