** Consulting firm Ricardo RCDO.L shares up 25.7% at 420.4p
** Stock on track for its biggest one-day pct gain since March 2020
** WSP Global WSP.TO to acquire co for an enterprise value of 363.1 million pounds ($488.99 million)
** WSP's acquisition values RCDO at about 281 million pounds
** Ricardo shareholders to receive 430p/shr
** Science Group SAGS.L, which holds about 21.8% of the voting rights in RCDO, said it supports WSP's offer and will sell a 20% stake to WSP for about 53.5 million pounds
** Science Group did not immediately respond to Reuters' request for comment
** YTD, RCDO down nearly 20%, including session's move
($1 = 0.7426 pounds)
(Reporting by Nithyashree R B in Bengaluru)
((NithyashreeRB@thomsonreuters.com))