把4.5:6化成最簡(jiǎn)整數(shù)比是________,比值是________.
3:4
分析:(1)根據(jù)比的性質(zhì)把4.5:6的前項(xiàng)和后項(xiàng)同時(shí)乘上2先化成9:12,再比的前后項(xiàng)同時(shí)除以3化成最簡(jiǎn)比,最簡(jiǎn)比是指比的前項(xiàng)和后項(xiàng)是互質(zhì)數(shù)的比;
(2)用最簡(jiǎn)比的前項(xiàng)除以后項(xiàng)即得比值;據(jù)此進(jìn)行化簡(jiǎn)并計(jì)算.
解答:(1)4.5:6,
=(4.5×2):(6×2),
=9:12,
=3:4;
(2)4.5:6,
=3:4,
=3÷4,
=
;
故答案為:3:4,
.
點(diǎn)評(píng):此題考查化簡(jiǎn)比和求比值的方法,要注意區(qū)分:化簡(jiǎn)比是根據(jù)比的基本性質(zhì)進(jìn)行化簡(jiǎn)的,結(jié)果仍是一個(gè)比;求比值是用比的前項(xiàng)除以后項(xiàng)所得的商,結(jié)果是一個(gè)數(shù),可以是小數(shù)、分?jǐn)?shù)和整數(shù).