` color{#e6f0ff}{@}color{#c7ddff}{T}color{#99c2ff}{o}color{#66a3ff}{r}color{#3385ff}{a}color{#0066ff}{U}color{#0044cc}{F}color{#002d80}{O}color{#001b4d}{@} `

` a) 25 + 37 + ( - 25 ) + 63 `

` = ( 25 - 25 ) + ( 37 + 63 ) `

` = 0 + 100 `

` = 100 `

` b) ( - 15 ) + 28 + 15 - 18 `

` = ( - 15 + 15 ) + ( 28 - 18 ) `

` = 0 + 10 `

` = 10 `

` c) 125 * 8 * 5 `

` = ( 125 * 8 ) * 5 `

` = 1000 * 5 `

` = 5000 `