Well I guess with the latest update now we have to pay for app plus to see the step by step and that is a big no no. For 1st problem, it is absolutely free but if you have to see steps for same model sums, then pay.
To insert a formula in Word, use the Alt and = hotkeys. This creates a special field for entering a mathematical expression. To type “greater than or equal to” in this field, just enter >= in