Excel: Alternative to CEILING for rounding to nearest value

Question

Normally I ask about work stuff so here's something different. To approach my new year's resolution in the nerdiest way possible, I'm creating a gym program in an excel file. I'll be doing ramped sets, which means each set I increase the weight be 10%. The formula I'm using allows a base weight (e.g. last week's max) to be entered, and calculates all the previous sets, rounded, up or down, to the nearest 2.5kg (1.25kg plates on each side of a bar; the smallest increment available).

=CEILING(($B13 - ($A$2 * 0.1)) - 1.25, 1.25 * 2)

In this formula, B13 is the next set after this one, and A2 is the base weight. So each set is 10% of the base weight less than the set after it, rounded to the nearest 2.5kg by the CEILING function.

Here's the kicker: the device I'll be taking with me is a Windows Phone 7 (I know, I know!). Its Excel program apparently doesn't support the CEILING function (or FLOOR). Is there a way to achieve this using the supported formulas, which according to MS Support are:

ABS, ACOS, AND, ASIN, ATAN, ATAN2, AVERAGE, CHOOSE, COLUMNS, CONCATENATE, COS, COUNT, COUNTA, COUNTBLANK, COUNTIF, DATE, DATEVALUE, DAVERAGE, DAY, DCOUNT, DCOUNTA, DDB, DEGREES, DGET, DMAX, DMIN, DPRODUCT, DSTDEV, DSTDEVP, DSUM, DVAR, DVARP, ERROR.TYPE, EXACT, EXP, FACT, FIND, FV, HLOOKUP, HOUR, IF, INDEX, INT, IRR, ISBLANK, ISERR, ISERROR, ISLOGICAL, ISNA, ISNONTEXT, ISNUMBER, ISTEXT, LEFT, LEN, LN, LOG, LOG10, LOOKUP, LOWER, MATCH, MAX, MID, MIN, MINUTE, MOD, MONTH, N, NA, NOT, NOW, NPER, NPV, OR, PI, PMT, POWER, PRODUCT, PROPER, PV, RADIANS, RAND, RANK, RATE, REPLACE, REPT, RIGHT, ROUND, ROWS, SECOND, SIN, SLN, SQRT, STDEV, STDEVP, SUBSTITUTE, SUM, SUMIF, SUMPRODUCT, SYD, T, TAN, TIME, TIMEVALUE, TODAY, TRIM, TRUNC, UPPER, VALUE, VAR, VARP, VLOOKUP, YEAR, FALSE, and TRUE.

And for those of you who were wondering, no, I swear I'm not as lonely as I must sound.

Answer 1

It should work with the ROUND function, no? Just divide your value by 2.5, round it to the nearest integer and multiply it again by 2.5