float 类型的数据如何存进 NSArray NSMutableArray里面

//存入

      for (NSDictionary *dic in self.lrcList) {

        int i = 0;

        NSString *timeStr = [dic objectForKey:@"lrctime"];

        NSArray *array = [timeStr componentsSeparatedByString:@":"];//把时间转换成秒

        float currentTime = [array[0] floatValue] * 60 + [array[1] floatValue];

        NSNumber *number = [NSNumber numberWithFloat:currentTime];

        //[timearray addObject:number];

        timearray[i]=number;

        i++;

}

//取出

[[timearray objectAtIndex:_numberOfLrc] floatValue]